Okay, that was an admittedly "dark"-sounding title, but it's perfectly appropriate for today's topic...How to get- and keep- your water as tinted as possible. Or, at least, what materials would do the best job in terms of "color production."
We as a group are kind of obsessed with this.
And yeah, it's a good question!
Now, first off- let's all remember that the color of the water has absolutely NO relationship to its pH or carbonate hardness. It just doesn't. You can have water that looks super dark brown, yet has a pH of 8.5 or whatever. And conversely, it's just as possible to have crystal clear blue-white water that's soft, and has a pH of 4.5. We have to get beyond the social media-style "blackwater" definition, which seems to be, "If the water is tinted, it's a blackwater aquarium!"
Now, look, if you just want the nice color but could care less about the pH and hardness, that's fine. For the benefit of the hobby as a whole, please don't perpetuate the confusing narrative about blackwater aquariums by telling others that you have "blackwater." You have a "tinted" aquairum.
And that's just fine.
So, yeah-I'm not going to launch into a long drawn out description today about how ecologists define "blackwater" and what specific chemical characteristics make it up- we've covered it enough over the years...you can deep dive here or elsewhere to get that.
Okay, micro-rant over. Let's get back to the topic.
Remember, this piece is not about how to make blackwater...It's a little more superficial than that...it's about creating an aquarium with color and maintaining it.
First off, one of the "keys" to getting your color that lovely brown is to select the right types and quantities of botanical materials to assist. Now, I'll be the very first to raise my hand and call BS on anyone who claims to have a perfect "recipe" for how many Catappa leaves per liter or whatever you must use to achieve a specific color. Sure, you could come up with some generic recommendations, but they're not always applicable to every tank or situation.
Yes...there are simply so many variables in the equation- many which we probably haven't even considered yet-that it would be simply guessing. Just like Nature, to some extent...
What I can do is recommend some materials which we have found over the years to generally impart the most reliable and significant color to water. In no particular order, I'll give you my thought on a few of my personal faves. There are a lot more, but these are some that consistently show up on my "fave" list.
Yep, you heard me. One of the very best sources of tint-producing tannins in our aquariums is wood. I've told you many times, wood imparts tannins, lignin, and all sorts of other "stuff" from the exterior surfaces and all of those nooks and crannies that we love so much into the water.
Now, I don't know about you, but I'm always amused (it's not that hard, actually) by the frantic posts on aquarium forums from hobbyists that their water is turning brown after adding a piece of wood. I mean- what's the big deal?
Oh, yeah, not everyone likes it...I forgot that. 😂
The reality, though, as you probably have surmised, is that wood will continue to leach tannins to a certain extent pretty much for as long as it's submerged. As a "tinter", I see this as a great advantage in helping establish and maintain the blackwater look, and to impart humic substances that are known to have health benefits for fishes.
Some wood types, like Mangrove ( a wood we don't have at the moment), tend to release more tannins than others over long periods of time. Other types, like "Spider Wood", will release their tannins relatively quickly, in a big burst. Some, such as Manzanita wood, seem to be really "dirty", and release a lot of materials over long periods of time. All will recruit fungal growths and bacterial biofilms.
And the biocover on the wood is a unique functional aesthetic, too, as we rant on and on about here!
I'm a huge fan of tree bark to impart not only color, but beneficial tannins into the water. Because of its composition and structure, bark tends to last a very long time when submerged, and tends to impart a lot of color to the water over the long term.
And to be quite honest, almost all of the bark products we've played with over the years seem to work equally as well. The real difference in bark is the "form factor" (appearance) and the color that they impart to the water over time. Some, such as Red Mangrove bark or Cutch bark, will impart a much deeper, reddish-brown tint to the water than say, an equal quantity of catappa bark. And our soon-to-be-released Ichnocarpus bark really packs in this reddish brown color! You're gonna love this stuff!
Ounce for ounce, gram for gram, I've always felt that various types of bark always impart the most color to the water over almost any other materials.
These are very interesting, woody pods, derived from the outer "valve" of the fruit of the Swietenia macrophylla tree, which hails from a wide range of tropical locales (although native to Brazil), and are just the sort of thing you'd find floating or submerged in a tropical jungle stream. Often called "Skyfruit" by locals in the regions in which they're found because they hang from the trees- a name we fell in love with!
These botanicals can leach a terrific amount of tannins, akin to a similar-sized piece of Mopani wood or other driftwood. They are known to be full of flavonoids, saponins, and other humic substances, which have known positive health effects on fishes. Like bark, it lasts a good long time and recruits some biofilms and fungal growths for good measure.
Live Oak Leaves/Magnolia Leaves
Despite their humble North American origins, these leaf types impart more color, ounce per ounce, than just about any of our fave tropical leaves. And they both last very long time...Like, I've had specimens of live oak leaves stay intact for several months!
It's really important to think of leaves as not just a "coloring agent" for your water, but as a sort of biological support mechanism for your burgeoning ecosystem. They actively recruit fungi, bacterial biofilms, and other microorganisms which enrich the overall aquatic environment in your tank.
Alder cones (Aalnus glutinosa and Alnus incana) and Birch cones (Betula occidentalis), have been widely utilized by aquarium hobbyists in Europe for some time. Betta and ornamental shrimp breeders are fond of the tannins released into the water by these cones, and their alleged anti fungal and antibacterial properties. There has also been much study by hobbyists about the pH reduction attributes of these cones, too.
A study done a few years back by a Swedish hobbyist using from one to six cones in a glass containing about 10 ounces of tap water, with a starting ph of around 8.12, was able to affect a drop to 6.74 with one cone after about two weeks, 4.79 with 2 cones after two weeks, and an amazing 3.84 with 6 cones after the same time period! The biggest part of the drop in pH occurred in the first 12 hours after immersion of the cones!
Now, I'm the last guy to tell you that a bunch of cones is the perfect way to lower pH, but this and other hobby-level studies seem to have effectively have demonstrated their ability to drive pH down in "malleable" (soft) water...
Coconut-based products (Coco Curls, "Fundo Tropical", "Substrato Fino")
There's something about coconuts...The materials which are derived from the husks of coconuts seem to produce a significant amount of tannins and impart color to the water. Of course, "Substrate Fino" and "Fundo Tropical" are smaller, or finer-textured materials which work primarily as "substrate enhancers", and not strictly as "color-producing agents", because there is an initial "burst", which subsides over time.
Now, one of the novel applications for these finer botanical materials to take advantage of their color producing ability is to place them in a fine mesh filter bag and allow water to flow around or through them, like filter media. Essentially, a more sustainable alternative to the old peat moss trick...
For an interesting look and some nice color, I'm a big fan of oak twigs. Oak has a nice bark which imparts a deep brownish/yellow color to the water and it's quite distinctive. There is a reason why our "Twenty Twigs" packs are pretty popular, and it's not just because you get a bunch of cool sticks!
When mixed with leaves and/or other botanical materials, not only do you get an incredible "framework" for a cool ecosystem, you get an incredible aesthetic as well!
Now, this is an absolutely cursory list.. I could have easily listed 10 or more items. No doubt, some of you hardcore enthusiasts are screaming at your screens now: "WTF Fellman, you didn't include_______!"
And of course, that's the beauty of natural materials...There are numerous options!
Another note on the colors to expect from various botanical materials. As you might suspect, many of the lighter colored ones will impart a correspondingly lighter tint to the water. And, some leaves, such as Guava or Loquat, also impart a more yellowish or golden color to the water, as opposed to the brownish color which Jackfruit and Catappa are known for.
A lot of you ask about things that impact how long the water retains it's tint.
This kind stuff is a big deal for us- I get it! Many hobbyists who have perhaps added some catappa leaves, "blackwater extracts", or rooibos tea to their water contact me asking stuff like why the water doesn't stay tinted for more than a few days. Now, I'm flattered to be a sort of "clearing house" for this stuff, but I must confess, I don't have all the answers.
So, "Why doesn't my water stay tinted, Scott?"
Well, I admit I don't know. Well, not for certain, anyways!
I do, however, have some information, observations, and a bunch of ideas about this- any of which might be literally shot to pieces by someone with the proper scientific background. However, I can toss some of these seemingly uncoordinated facts out there to give our community some stuff to "chew on" as I offer my ideas up.
Now, perhaps it starts with the way we "administer" the color-producing tannins.
Like, I personally think that utilizing leaves, bark, and seed pods is perhaps the best way to do this. I'm sure that you're hardly surprised, right? Well, it's NOT just because I sell these material for a living...It's because they are releasing tannins, humic substances, and other compounds into the water "full time" during their presence in the aquarium as they break down. A sort of "on-board" producer of these materials, with their own "half life" (for want of a better term!).
And, they also perform an ecological role, providing locations for numerous life forms (like fungal growths) surface area upon which to colonize. They become part of the ecosystem itself. A few squirts of "blackwater extracts" won't do that, right?
The continuous release of tint-producing compounds from botanical materials keeps things more-or-less constant. And, if you're part of the "school" which leaves your botanicals in your aquarium to completely break down, you're certainly getting maximum value out of them! And if you are continuously adding/replacing them with new ones as they completely or partially break down, you're actively replenishing and adding additional "tint-producing" capabilities to your system, right?
There is another way to "keep the tint" going in your tanks, and it's pretty easy. Now, those of you who know me and read my rambling or listen to "The Tint" podcast regularly know that I absolutely hate shortcuts and "hacks" in the aquarium hobby. I preach a long, patient game and letting stuff happen in its own time...
Nonetheless, there ARE some that you can employ that don't make you a complete loser, IMHO.😆
When you prepare your water for water changes, it's typically done a few days to a week in advance, so why not use this time to your advantage and "pre-tint" the water by steeping some leaves in it? Not only will it keep the "aesthetics" of your water ( can you believe we're even talking about "the aesthetics of water?") consistent (i.e.; tinted), it will already have humic substances and tannins dissolved into it, helping you keep a more stable system.
Obviously, you'd still check your pH and other parameters, but the addition of leaves to your replacement water is a great little "hack" that you should take advantage of. (Shit, I just recommended a "hack" to you...)
It's also a really good way to get the "look" and some of the benefits of blackwater for your system from the outset, especially for those of you heathens that like the color of blackwater and despise all of the decomposing leaves and seed pods and stuff!
So, if you're just setting up a brand new aquarium, and have some water set aside for the tank, why not use the time while it's aging to "pre-tint" it a bit, so you can have a nice dark look from day one? It's also great if you're setting up a tank for an aquascaping contest or other same-day club event that would make it advantageous to have a tinted tank immediately.
I must confess that yet another one of the more common questions we receive here from hobbyists is, "How can I get the tint in my tank more quickly?"- and this is definitely one way!
How many botanicals to use to accomplish this?
Well, that's the million dollar question.
It all gets back to the (IMHO) absurd "recommendations" that have been proffered by vendors over the years recommending using "x" number of leaves, for example, per gallon/liter of water. There are simply far, far too many variables- ranging from starting water chem to pH to alkalinity, and dozens of others- which can affect the "equation" and make specific numbers unreliable at best.
We did, too, in the early days of Tannin. And it was kind of stupid really. There just is no hard-and-fast answer to this. Every situation is different. You need to kind of go with your instinct. Go slowly. Evaluate the appearance of your water, the behaviors of the fishes...the pH, hardness, TDS, nitrate, phosphate, or other parameters that you like to test for.
It's really a matter of experimentation.
I'm a much bigger fan of "tinting" the water based on the materials in the aquarium. Letting Nature have at it. The botanicals will release their "contents" at a pace dictated by their environment. And, when they're "in situ", you have a sort of "on board" continuous release of tannins and humic substances based upon the decomposition rate of the materials you're using, the water chemistry, etc.
Replacement of botanicals, or addition of new ones, as we've pointed out many times, is largely a subjective thing, and the timing, frequency, and extent to which materials are removed or replaced is dependent upon multiple factors, ranging from base water chemistry to temperature, to the types of aquatic life you keep in the tank (ie; xylophores like certain Plecos, or strongly grazing fishes, like Headstanders, will degrade botanicals more quickly than in a tank full of characins and such).
(The part where Scott bashes the shit out of the idea of using "blackwater extracts" and Rooibos tea. This could get nasty!)
If you haven't heard of it before, there is this stuff called Rooibos tea, which, in addition to bing kind of tasty, has been a favored "tint hack" of many hobbyists for years. Without getting into all of the boring details, Rooibos tea is derived from the Aspalathus linearis plant, also known as "Red Bush" in South Africa and other parts of the world.
(Rooibos, Aspalathus linearis. Image by R.Dahlgr- used under CC-BY S.A. 2.5)
It's been used by fish people for a long time as a sort of instant "blackwater extract", and has a lot going for it for this purpose, I suppose. Rooibos tea does not contain caffeine, and and has low levels of tannin compared to black or green tea. And, like catappa leaves and other botnaicals, it contains polyphenols, like flavones, flavanols, aspalathin, etc.
Hobbyists will simply steep it in their aquariums and get the color that they want, and impart some of these substances into their tank water. I mean, it's an easy process. Of course, like any other thing you add to your aquarium, including leaves and botanicals, it's never a bad idea to know the impact of what you're adding.
Like using botanicals, utilizing Rooibos tea bags in your aquarium requires some thinking, that's all.
The things that I personally dislike about using tea or so-called "blackwater extracts" are that you are simply going for an effect, without getting to embrace the functional aesthetics imparted by adding leaves, seed pods, etc. to your aquarium as part of its physical structure and ecology, and that there is no real way to determine how much you need to add to achieve______.
Obviously, the same could be said of botanicals, but we're not utilizing botanicals simply to create brown water or to target specific pH parameters, etc. We're trying to create an ecology that is similar to what you'd see in such habitats in Nature.
Yet, with tea or commercial blackwater extracts, you sort of miss out on replicating a little "slice of Nature" in your aquarium. The building of an ecosystem. Which is why we call this the botanical method. It's not a "style" of aquascaping! And of course, it's fine if your goal is just to color the water, but it's more of an aesthetically-focused aquarium at that point.
I also understand that some people, like fish breeders who need bare bottom tanks or whatever- like to condition water without all of the leaves and twigs and nuts we love. They want the humic substances and tannins, but really don't need/want the actual leaves and other materials in their tanks.
And, when it comes to tea and these commercial extracts, I don't think the stuff lasts all that long. I personally believe that the tint-producing tannins in "tea" are potentially taken up quickly by substrate materials, filter media, etc. And unless you're keeping tea bags in your tank on a continuous basis, you'll always experience some "color loss" after some period of time.
Yes it works to impart some color and tannins. Creating infusions or extracts is useful, if you understand their purpose and limitations. They have a place in the hobby for sure.
It's why we got into the game with our botanical-based "Shade" products. We're currently sold out and are working with our supplier on a reformulated version. Seems as though we need to make a "darker" mix!
On the other hand, if you're trying to replicate the look and function (and maybe some of the parameters) of THIS:
You won't achieve it by using THIS:
It's simply another shortcut.
Not good or bad. Just a way to get the end "effect" faster, and without the other collateral benefits we discussed.
And look, I understand that we are all looking for the occasional shortcuts and easier ways to do stuff. And I realize that none of what we proffer here at Tannin is an absolute science. It's likely more of an "art" at this point, with a little science behind it.
Think about it: There is no current way available to the hobby to test for "x" types or amounts of tannins (of which there are hundreds of types) in aquariums. I mean, there are tannin test kits, but they're used for wine making and such...Perhaps there is some tangential application for our purposes, but I'm not really sure what practical information. we could extract from the results.
And, I have not found a study thus far which analyzed wild habitats (say, Amazonia) for tannin concentrations and specific types, so we have no real model to go on.
The best we can do is create a reasonable facsimile of Nature.
And, in Naturę, a lot of the tint in blackwater environments comes from dissolved fulvic and humic acids from...soils. Yeah, geology is the key, IMHO, to truly "realistic" blackwater habitats. This is why I've been very picky on sourcing the materials and figuring out recipes for our NatureBase sediment substrates. They are intended to support these types of systems.
Understanding substrates and their role in both the physical environment and the ecology of our aquariums is still a wildly under-appreciated concept in the aquarium hobby, IMHO. We'll keep coming back to this in the future, I'm certain.
And keeping the water tinted is something that many botanical method aquarists are interested in. This wonderful "collateral benefit" of our approach is something that's easy to get addicted to!
Now, all of these ideas are okay to impart some color to your water. Some do more, as we've discussed ad nauseam. And none of them will work to full advantage if your aquarium is removing them as fast as you're imparting them into the water. So, go easy on chemical filtration media like carbon. I didn't say NOT to use them...Just don't use a ton of them! Use less than what the manufacturer recommends.
What about plants?
Well, I have a theory about plants and tannins...
First off, as you know by now, you absolutely can keep plants in blackwater aquariums. We've talked about this a million times over the years. And yet, interestingly, you can't always keep "blackwater conditions" (at least, color-wise) in planted aquariums! There has been much geeky discussion on this topic.
Tannin are interesting things. Think about this:
Tannins are known to bind up heavy metals and minerals. The roots of aquatic plants prefer to take up bound-up minerals and metals...So, another theory of mine is that heavily planted tanks do actually remove some of the visual "tint" (ie; the tannins) from the water via uptake from their roots.
Make sense? Maybe?
Okay, I could go on and on all day throwing out all sorts of theories and unsubstantiated (via lab tests and rigorous studies, anyways) ideas on this topic...But I think I gave you enough here to get the party started. I encourage you to do some homework. We need to ask these questions to people who really understand the chemistry here. I think that there might be some good answers out there.
And, back to the "color thing" to close on here...
I admit, visual "tint" is probably THE single most superficial aspect of what we experience with botanical-method aquariums- but the most obvious, and likely the most impactful to the casual hobbyist or observer.
It's just as important to understand the collateral benefits of utilizing botanical materials- a subject we've discussed dozens of times here. However, in the end, it's the look of your aquarium that is what you have to experience each and every day, and if having an understanding of which materials can bring you the aesthetic experience you're after in a more effective way- well, then this is a worthwhile discussion, right?
I think that it is.
Stay curious. Stay resourceful. Stay enthusiastic. Stay observant. Stay appreciative. Stay tinted...
And Stay Wet.
Time to hit on another of my fave topics regarding botanical method aquariums; one that we've talked about before- yet one that is still new and exciting to many of us, and perhaps clouded at times with a lot of misinformation, too.
We're talking about botanically-supplemented substrates!
For far too long in the aquarium hobby, I think that we've treated aquairum substrates as simply an afterthought. I mean, there are all sorts of sands and gravels on the market today, but I think that we sort of take them for granted- or at the very least, we treat them as a "requirement" when setting up a tank, and move on to other, more "exciting stuff": "Sand added, check. Time to select the wood!"
That sort of thing.
One of the most "liberating" things we've seen in the botanical-method aquarium niche is our practice of utilizing the bottom itself to become a feature aesthetic point in our aquariums, as well as a functional mechanism for the inhabitants.
"Oh, shit, he's talking about that 'functional aesthetic' thing again!"
Yeah. Yes I am. 😎
Because I think that there are a lot of "missed opportunities" to do something cool with substrates in our tanks. Opportunities to make it a much more important part of the aquarium.
When you look at it from our rather biased perspective, and from a strictly aesthetic sense, the bottom itself becomes a big part of the aesthetic appeal of the aquarium. You may not focus on it, observationally, but it's hugely important. And of course, I see the bottom of the aquarium as more than just sand or whatever. Rather, it's a important component of the aquarium habitat, with the botanical materials placed upon or mixed into the substrate- or, in some cases, becoming the substrate!
These materials form an attractive, texturally varied "microscape" of their own, creating color and interest. In addition to be being comprised of the usual sands and gravels, we can be adding bits of botanicals, root pieces, twigs, leaves, etc. into the mix.
Again, the focus isn't just on aesthetics.
It's about creating a habitat for the fauna which help "run" our tanks!
Much like in Nature, the materials that we place on the bottom of the aquarium will become an active, integral part of the ecosystem. From a "functional" standpoint, bottoms comprised of supplemented with a variety of botanical materials form a sort of "in-tank refugium", which allows small aquatic crustaceans, fungi, and other microorganisms to multiply and provide supplemental food for the aquarium, as we've touched on before.
So, the idea of creating rich, diverse botanical-influenced substrates for the purpose of infusing tannins, humic substances, and other compounds- as well as creating a "matrix" for the growth and propagation of beneficial micro and microfauna is pretty appealing to me.
Using a botanically-infused substrate to create a unique, ecologically diverse, functional, and aesthetically interesting affect on the aquarium- even one that doesn't have aquatic plants in it- is a sort of different approach.
Functionality. Interest. Aesthetics. Stability. They're all there!
Nature provides no shortage of features which can provide inspiration for unique aquariums.
Think about the materials which accumulate on and in the substrates of natural aquatic habitats, and why they accumulate in the first place. Well, typically, in addition to soils and leaves, you'll see sediments, pieces of plant roots, bits of twigs and bark, and the occasional seed pod. Almost all of this material arrives in these bodies of water from the surrounding terrestrial environment.
Some of it is present on forest floors, and when nearby streams overflow, inundating the once dry floor, these materials become part of the aquatic environment, influencing both the structure and the ecology of the habitat. Other materials, like sediments, are the product of hydrology and erosion- rocks ground down over eons by water; or soils- which find their way into streams during periods of intense rain, with the resulting material distributed over vast distances by current.
The beauty of Nature is that She uses pretty much everything that is thrown at Her. Fishes and other organisms feed directly upon some of this material, or on the other life forms (small crustaceans, insects, fungal growths) which live among it. The bottom of streams and other becomes a vibrant, ecologically diverse habitat, which supports a tremendous amount of life at many levels.
And we just throw bag of aquarium sand or gravel on the bottom of our tanks...and move on!
Like, WTF is a matter with us fish geeks? There is HUGE opportunity here! We need to give a lot more thought to what goes on the bottom of our aquariums! Instead of becoming a literal "placeholder" in our tanks, substrate should become the ecological "backbone"- and a (functionally aesthetic) foundation of our miniature aquatic ecosystems- just like it is in Nature!
Now, the first "pushback" we hear from critics of this type of approach in aquariums is that it will result in all sorts of problems- ranging from suppressed pH to high levels of nitrates, or even pockets of hydrogen sulfide and other nasty stuff accumulating.
I think that this is an incredible over-reaction and grounded in not fully thinking through why we are creating substrates like this in the first place.
In Nature, the leaf litter "community" of fishes, insects, fungi, and microorganisms is really important to the overall tropical environment, as it assimilates terrestrial material into the blackwater aquatic system (and, by doing this, acts to reduce the loss of nutrients to the forest which would inevitably occur if all the material which fell into the streams was washed downstream...)
The key point: These materials foster the development of life forms which process it. Stuff is being used by life forms.
It's the same in our aquariums.
And bits of botanical materials and such not only provide a physical substrate upon which these organisms can grow and multiply as they process it- they provide a sort of "on board nutrient processing center" within the aquarium.
If you approach this "substrate enrichment" idea holistically, rather than just from some warped aesthetic mindset, creating and managing such a system is not at all difficult or dangerous. In fact, you don't really need to give it all that much thought in a well-managed aquarium, once it's set up.
I realize that experimenting with these unusual substrates requires not only a sense of adventure, a direction, and some discipline- but a willingness to accept and deal with an entirely different aesthetic than what we know and love. And this also includes pushing into areas and ideas which might make us uncomfortable, not just for the way they look, but for what we are told might be possible risks.
One of the things that many hobbyists ponder when we contemplate creating deep, botanical-heavy substrates, consisting of leaves, sediment, bark, and other botanical materials is the "buildup of hydrogen sulfide", CO2, and other undesirable compounds within the substrate.
Well, sure, I can't entirely "diss" fellow hobbyists for having this fear. It does make sense that if you have a large amount of decomposing material in an aquarium, then some of these compounds are likely to accumulate in heavily-"active" substrates. The big "bogeyman" that we all seem to zero in on in our "sum of all fears" scenarios - the one which keyboard warriors on the forums will pounce on- is an accumulation of deadly hydrogen sulfide, which results from bacterial breakdown of organic matter in the total absence of oxygen.
Let's think about this for just a second.
In a botanical bed with materials placed on the substrate, or loosely mixed into the top layers, will it all really "pack down" enough to the point where there is a complete lack of oxygen and we develop a significant amount of this reviled compound in our tanks? Are we managing tanks in such a way as to encourage no circulation whatsoever?
I think that we're more likely to see some oxygen in this layer of materials, and in fact, I can't help but speculate- and it IS just speculation- that actual de-nitirifcation (nitrate reduction), which lowers nitrates while producing free nitrogen, might actually be able to occur in a "deep botanical" bed.
And it's certainly possible to have denitrification without dangerous hydrogen sulfide levels. As long as even very small amounts of oxygen and nitrates can penetrate into the substrate this will not become an issue for most systems. I have yet to see a botanical-method aquarium where the material has become so "compacted" as to appear to have no circulation whatsoever within the botanical layer.
Now, sure, I'm not a scientist, and I base this on close visual inspection of numerous aquariums, and the basic aquarium-standard chemical tests I've run on my systems under a variety of circumstances. As one who has made it a point to keep my botanical method aquariums in operations for very extended time frames, I think this is significant. The "bad" side effects we're talking about should manifest over these longer time frames...and they just haven't.
Yeah- in my experience, based on literally a lifetime of playing with all sorts of combinations of materials in dozens and dozens of my aquariums' substrates ('cause I've always been into that stuff!), I cannot attribute a single environmental lapse, let alone, a "tank crash", as a result of such additions.
A well-managed substrate, in which uneaten food and fish feces are not allowed to accumulate to excess, and in which regular nutrient export processes are embraced, rather than decimated by constant interference (ie; siphoning) it's not an issue, IMHO. When other good practices of aquarium husbandry (ie; not overcrowding, overfeeding, etc.) are empIoyed, a botanically-"enriched" substrate can enhance- not inhibit- the nutrient processing within your aquarium and help maintain high water quality for extended periods of time.
Like many of you, I have always been a firm believer in some forms of nutrient export being employed in every single tank I maintain. Typically, it's regular water exchanges. Not "when I think about it', or "periodically", mind you.
Nope, it's weekly.
Now look, I'm not saying that you can essentially disobey all the common sense husbandry practices we've come to know and love in the hobby (like not overcrowding/overfeeding, etc.) and just change the water weekly and everything's good. And I'm not suggesting that the only way to succeed with adding botanical materials to the substrate is to employ massive effort at nutrient export; the system otherwise teetering on a knife's edge, with disaster on one side and success on the other.
It's not that binary.
Our aquariums are more resilient than that. If we set them up to be. Common sense aquarium management, with an eye towards how natural aquatic systems work, is key, IMHO.
Of course, an aquarium is NOT a stream, river, etc. However, the same processes and "rules" imposed by Nature that govern the function of these wild ecosystems apply to our little glass and acrylic boxes. It's simply a matter of nuance in management and understanding how these wild habitats work on a basic level.
I'd love to keep us in the mindset of thinking about our aquariums as little "microcosms", not just "aquatic dioramas."
Think about this: The idea of a substrate "enriched" with botanical materials is completely in line with the practices of a "dirted" planted aquarium. In our case, not only will there be an abundance of material for microorganisms and crustaceans to forage and multiply among, trace elements and essential plant nutrients will also be present in such a substrate. And, of course there will be the constant addition of tannins and humic substances into the water, which provide many known benefits for fishes as well.
The best of both worlds, I think.
Again, it's not about creating a cool Instagram-ready "look."
It's about trying to create an entire aquatic ecosystem.
Embracing and fostering not just the look, but the very processes and functions which take place in natural aquatic systems. Is it as simple as crushing some leaves, adding some coconut-based material, covering it up with sand and you have an "instant tropical stream?" No, of course not. There is no such "magic bullet!" You need to look at things sort of "holistically"- with an eye towards nutrient export and long-term maintenance.
For those of you who are adventurous, experimental, diligent, and otherwise engaged with managing and observing your aquariums, I think this process offers amazing possibilities. Not only will you gain some fascinating insights and the benefits of "on-board" nutrient export/environmental "enrichment"- you will also get the aesthetics of a more natural-looking substrate as well. (Let's face it, no matter how "function first" we feel that we are, everyone likes a nice-looking aquarium, right?)
So, the best way to "enrich" (for want of a better term) your substrate is to add the botanical materials and sediments before you fill the tank up with water. In the case of leaves, bits of botanicals, etc., you'd want to have boiled/steeped them previously, so that they are rid of any surface contaminants, and to assure that their tissues are saturated enough to get them to sink immediately upon submersion.
There is no set "process" for this, other than to mix these materials into the upper layers of substrate as you add them. You will just sort of know when you've achieved the look and texture that pleases you (that's the "aesthetic" part!), and take comfort in knowing that just about any amount of these materials that you're adding to your system will help accomplish the "functional" aspect.
Once your substrate is in place, Nature takes over and the materials develop that lovely "patina" of fugal growth, biofilms and microbial colonization, and start breaking down. Some may be moved about by the grazing activities of resident fishes, or otherwise slowly redistributed around the aquarium.
A literal "active substrate", indeed! Yet, something that is fascinating and beautiful for those who give the idea a shot!
At this point, I have to admit that there are many hobbyists who will never find any sort of appeal whatsoever in a botanically-enriched substrate, dark and complex, filled with all sorts of "stuff" besides just sand. The so-called "Nature Aquarium" cult crowd, or the truly "artistic" aquascaping people, for example, will likely never approve of this idea, because it looks "dirty" to them, and because some of the aesthetic and management "work" is being "ceded" to Nature. They need to be in control.
I admit, the simple practice of adding "botanical stuff" into our aquariums is not some "high concept thing." However, the impacts on the water chemistry and overall aquatic environment- not to mention, on our fishes- are profound, fascinating, and real!
Being careful and taking the time to clean, prepare, and add botanicals to your aquarium in a measured manner always yields a better outcome. Going slowly also gives you the opportunity to address any issues that you might have before they become critical, especially when you're experimenting with some of these ideas.
It just makes sense to be patient. The rewards are so great.
From a maintenance standpoint, it's pretty straightforward. You monitor your environmental parameters regularly, and conduct routine water exchanges, taking care not to siphon aggressively from the substrate. You simply don't want to disrupt the very processes within the substrate that you're trying to foster. And trust me, your fishes will spend a lot of time foraging among it.
Much like what occurs spontaneously in Nature, the materials that we deliberately place on the bottom of the aquarium will become an active, integral part of the ecosystem.
Like so many things we discuss here, I admit that simply don't have all the answers about every aspect of botanically-supplemented substrates. There is a ton to learn! That's part of the joy of this process- sort of figuring out why and how it works as you're enjoying the success!
Playing with ideas like botanically supplemented substrates truly pushes the boundaries between what we do al the time in the hobby, and those outer regions where few have tread before. There will be challenges, discoveries..and rewards for taking this road less travelled.
And that's part of the fun, isn't it?
Stay creative. Stay brave. Stay curious. Stay diligent...
And Stay Wet.
Our approach to aquarium keeping is as much a "mindset" as it is a practice. And, although the practical techniques are relatively easy to grasp and execute, the philosophical components can be confusing and seem a bit contradictory at times.
We preach radical patience, yet completely embrace the idea of dramatically changing things within the greater "mindset."
Yeah, you should just do what feels right to you.
And sometimes, that means creating an aquarium which doesn't look anything like you'd want it to until long after it's been established. Other times, it means tearing stuff apart immediately and "re-directing" your tank based on a different vision.
Yet, I always urge you to take a slightly longer view of what''s going on in your tank. Not to rush to completely tear your aquarium apart just because it doesn't seem to be getting to where you want it to go right after you set it up.
Stuff takes time.
Looking back on some of my favorite tanks that I've executed in the past few years, it becomes increasingly obvious to me that these systems really didn't completely hit that "look and feel" that I want until long after they'd evolved naturally...however long that took. It seems that , in the botanical-method aquarium, stuff needs to acquire a "patina" of biofilm, a "stain" from the tannins, and decomposition of botanical materials needs to really begin before one of these systems turns "functional" as well.
That's part of why using aesthetics only as an evaluation criteria for a successful botanical-method aquairum falls a bit short, IMHO.
I mean, every new botanical-method tank likely looks cool to a broader swatch of the aquarium world from day one, if you're just using superficial aesthetics as your metric...But the long-established ones stand out for what they really are. After 4-6 months, that's when things get really special. After Nature has done a lot of the real "work" on the tank.
The decomposition of materials in water impacts our aesthetics greatly, as we all know by now. And that is what's so intriguing. The crisp leaves and dry, lifeless twigs that you submerge will evolve into a dynamic, ever-changing microcosm.
Every tank can get there.
Simply by exercisng patience, and letting your aquarium be.
I've long held that perhaps my fave botanical-method aquarium of all was the one I did about 3 years ago..an aquarium utilizing mangrove wood, extensive leaf litter, and catappa bark throughout. This is probably the only tank in recent years that I've truly regretted changing and moving on from! 😂
I knew what it was I wanted from the tank at the start, but it didn't look like much at first...It would have tested a lot of people's faith if they saw it in it's early stages!
It literally looked like shit for the first couple of months of it's existence: Slightly tinted water, a contrived-looking "campfire-like" wood stack, bare sand, and mostly intact botanical materials. I had to do a bunch of "iterations" with the hardscape to get it where I wanted it. It looked quite "contrived" at points, but I knew instinctively that if I waited it out, let Nature do Her thing- that the potential was huge in this tank.
Sure enough, a few months in, biofilms started forming. The wood acquired that "patina" we talk about so much. Leaves and botanicals broke down...And the water took on perhaps the most earthy-looking, deeply mysterious color I've seen in a botanical-influenced blackwater aquarium.
By some standards, the water in the tank could be described as almost "turbid"- taking on an appearance as though there were fine materials in the water column. Yet, the tank had a real magical appearance with the lighting; the fishes were as colorful, relaxed and happy as any I've ever seen, and the water parameters were spot-on and consistent for as long as the tank was set up.
The essence of "wabi-sabi", for sure. Transience, the ephemeral aspects of our botanicals...the wonders of Nature, embraced.
It just took a little time.
I could have "intervened" at a number of junctures- trying to "circumvent" these aesthetic "deviations" while the tank was evolving. However, I knew not to. I knew that the long-term gains from letting this system evolve would far exceed any "relief" I'd gain from siphoning out the biofilms, removing decomposing leaves, and clearing the water.
And, as usual- Nature delivered...because I didn't get in Her way.
We've done this numerous times with similar results. Inauspicious starts.
Botanical-method aquariums typically require more time to evolve than more "conventional" aquariums do. They are dependent upon the development of a specialized ecology, which includes fostering organisms like fungal growths and biofilms.This process can be "expedited" or manipulated a bit, but to achieve truly meaningful and beneficial results, you just can't rush stuff!
You can't interrupt it, either.
When you do, as we've learned, results can be, well- "different" than they would be if you allow things to continue on at their own pace. Not necessarily always "bad"- just not as good as what's possible if you relax and let Nature run Her course without interruption. Following a plan is never a bad idea; it can lead to some exciting destinations.
However, the ability to "pivot" and "go with the flow" is really important, too.
It's not always a bad idea to switch things around if you're suddenly inspired to do so. What I hate to see is when hobbyists attempt to "intervene" on the processes which are occurring in the tank- like the recruitment of biofilms and fungal growths, the breakdown of leaves, etc. THAT'S a problem, imho. You can change the "overall theme" without irrevocably interrupting Nature's processes.
Yeah, there IS a certain kind of "intervention" which I occasionally embrace myself. As I've previously discussed here, on occasion, I'll start to execute on an idea I've had, and very early (or sometimes, not so early) in the process, I'll completely lose interest in it for whatever reason (it can be anything from "not feeling it!" to "I hate that I can't hide that heater!"), and the desire to abort and move on to something else on my "to do list" beckons.
In general, however, I play a really long game.
One which acknowledges that the fact that our botanical-method aquariums evolve over very long periods fo time, not reaching the state that we perhaps envisioned for many months. My actions reflect this mindset. Unless there is some major emergency, about the only thing that I might do is to add a few more botanicals, re-arrange some wood, or just wait it out.
Of course, if you really are "not feeling it" (it happens!), does it mean tearing the whole thing apart and starting over?
You can change the "look" or aesthetic direction of an aquairum- fairly significantly- without disrupting its function.
One of the things I've done a lot in recent years when making big changes to aquariums is to keep the substrate layers from my existing tanks and "build on them." It makes a ton of sense, really. Why waste this goodness, just because the "theme" of the "new" tank is different than the existing one?
Your South American-themed tank won't be that much different if you change up the "hardscape" to turn it into s Southeast Asian-themed tank, while leaving the substrate layer intact, right?
In other words, I'm taking advantage of the well-established substrate layers, complete with their sediments, decomposing leaves and bits of botanicals, and simply building upon them with some additional substrate and leaves. I've done this many times over the years- and I'm sure a lot of you have, too-it's hardly a "game-changing" practice, but it's something not everyone talks about.
I believe that preserving and building upon an existing substrate layer provides not only some biological stability (ie; the nitrogen cycle), but it has the added benefit of maintaining some of the ecological diversity and richness created by the beneficial fuana and the materials present within the substrate.
I know many 'hobby old timers" might question the safety- or the merits-of this practice, mentioning things like "disturbing the bacterial activity" or "releasing toxic gasses", etc. A lot of 'em would rather have you simply remove this stuff altogether. It's "all or nothing" for them! I'm not sure how leaving the substrate layer intact is problematic. It doesn't "die." I believe that particular belief is steeped in "aquarium mythology", conflates a lot of different ideas and topics, and has generally been misapplied and misunderstood over the years.
I simply have never experienced any issues of this nature from this practice. Well maintained systems generally are robust and capable of evolving from such disturbances. And we're not really "disturbing" the substrate when we preserve it, are we? Moving around a few pieces of wood or rock might cloud the water a bit, but it's not wholesale disturbance of the substrate.
I see way more benefits to this practice than I do any potential issues.
Since I tend to manage the water quality of my aquariums well, if I say so myself, I have never had any issues, such as ammonia or nitrite spikes, by doing this- in fresh or saltwater systems. It's a logical way of maintaining stability and continuity- even in an arguably disruptive and destabilizing time!
This idea of a "perpetual substrate"- keeping the same substrate layer "going" in successive aquarium iterations- is just one of those things I believe that we can do to replicate Nature in an additional way.
Well, think about it for just a second. In Nature, the substrate layer in rivers, streams, and yeah, flooded forests and pools tends to not completely wash away during wet/dry or seasonal cycles.
Oh sure, some of the material comprising the substrate layer may get carried away by currents or other weather dynamics, but for the most part, a good percentage of the material- and the life forms within it- remains when the water recedes. Wind and weather add additional materials to the now terrestrial environment, which become part of the aquatic habitat when the waters return.
So, by preserving the substrate from the previous iteration of your aquarium, and perhaps "refreshing" it a bit with some new materials (ie; sand, sediment, gravel, leaves, and botanicals), you're essentially mimicking some aspects of the way Nature functions in these wild habitats!
And, from an aquarium management perspective, consider the substrate layer a living organism (or "collective" of living organisms, as it were), and you're sure to look at things a bit differently next time you "re-do" a tank!
I suppose, one could view the process of "perpetuating" the substrate almost like persuing "eternal youth"- it's not entirely possible to achieve, but you can easily embrace the idea of renewal and continuity within your aquarium. It's a very natural process. Perhaps it's even beneficial in some way over the long term?
Things change in Nature, some things are utilized elsewhere, and other things are preserved in situ. Nothing goes to waste.
Rather, stuff gets "folded" into the changing ecosystem. Leaves on the forest floor become a lush ecological niche for fungal growth and bacteria, and a grazing substrate for fishes when submerged. Tree branches become "attachment points" for epiphytic plants, sponges, and other aquatic life forms.
Nature is very efficient. We should take a cue from Her! "Disruption" is often a form of renewal and evolution in Nature.
Patience, as always, is the key ingredient here. Of course, this is a hobby, and it should be fun...and you should feel free to change stuff up if it's not. However, make it a point to consider your actions in the "big picture", and it takes on a greater significance.
You need to have an understanding that you're creating a dynamic environment, not simply an "aquascape." And it's constantly evolving- even when you're not ripping it apart! It's anything but "static"-sort of like a planted aquarium, but in reverse (rather than plants growing, the botanicals are, for want of a better word "diminishing")! At any given time, you'll have materials like leaves in various states of decomposition, seed pods, slowly softening, breaking down, and recruiting biofilms and a "patina" of fungal growth.
It begs the most fundamental of questions about our botanical method practice:
What happens over time in a botanical method aquarium? What changes occur along the way?
Well, typically, at its simplest, as most of you who've played with this stuff know, the botanicals will begin to soften and break down. Botanical materials are the very definition of the word "ephemeral." Nothing lasts forever, and botanicals are no exception! Pretty much everything we utilize- from Guava leaves to oak twigs- starts to soften and break down over time.
Most of these materials should be viewed as"consumables"- meaning that you'll need to replace them over time if you want maintain some environmental consistency. Again, perfectly analogous to what occurs in Nature.
You're not an "aquascaper" in the classic hobby sense when you play with these types of systems. Rather, you're a a sort of "superintendent" to Nature, helping Her do what she has done for eons. You're not simply an idle "passenger," either- you play an active role in conceiving, setting up, and maintaining such a system. You need to take some cues from Nature, and that often means simply standing by and observing as she does Her work and goes through Her process.
You learn. You evolve with your aquarium, on a very real level.
Sometimes, it requires intervention on your part- at least in your own mind, perhaps. Other times, it simply involves sitting back, letting things unfold, and observing patiently.
Watching a display aquarium evolve and sort of "find itself" naturally over time is proving to be one of the most enjoyable discoveries I've made in the hobby in decades. It's a mindset that I actually had in my youth- by necessity, because I had very limited resources except for time- yet lost as I grew into adulthood and "evolved" in the hobby. With more skills and economic resources, I could "do more"- but the reality is that it wasn't always the right thing.
It took me a few decades after hitting so-called "advanced" hobbyist status before it really hit me that, by simply studying the function of natural ecosystems, all of the answers I needed to be successful as an aquarist were right there! I just needed to figure out which questions to ask.
I'm still deep in that process, decades later!
By understanding that my aquariums are governed by the same "laws" which apply to natural aquatic ecosystems, and developing and following simple practices and husbandry routines to embrace this, and monitoring what's occurring in the tank (as opposed to constantly trying to intervene to "pre-empt" what we in the hobby have commonly perceived to be problems), I've personally had more beautiful, healthy and stable aquariums, and...more success than ever before.
Accepting that there is most definitely an elegant, yet complex ecological "dance" in our aquariums, and becoming an "active monitor" instead of an "active intervener" has added an enjoyable and rewarding aspect to my love of the hobby.
I think that this approach to the "dance" not only makes you a more engaged hobbyist, it gives you a remarkable appreciation for the long term evolution of an aquarium; an appreciation for the pace by which Nature operates, and the direction in which your aquarium ultimately goes.
By doing this, you get the enjoyment of seeing the "evolution" every day! Observing and enjoying the subtle nuances of your aquarium at every stage of its existence. With my "go slow" mindset and practice, the differences are subtle in the short term- the "payoffs" really more apparent over the longer term.
Again, it's okay to make changes- even significant ones- to the "theme" of your aquarium. However, it's simply not good practice to interfere with the processes which allow it to become what Nature ( and YOU, too, if you're honest with yourself) wants it to become.
I know, it does feel a bit "yin" and "yang"- like I'm pulling from both sides- telling you, on one hand, that it's okay to make significant changes to a tank, while simultaneously urging you to deploy extreme patience and an almost "sit back and relax" approach...These seemingly diametrically opposite actions actually work really well together when you have the "common denominator" of good intentions, vision, careful actions, and an appreciation for what Nature can do if we let Her.
This philosophy, like so many things I ask you to consider here- doesn't always seem to make any sense.
Until it does.
Be kind to yourself- and to Nature.
Trust that She'll guide your aquarium effectively along the way to its ultimate potential. She won't let you down. Even if you take a slight detour now and again.
Stay confident. Stay observant. Stay curious. Stay patient....
And Stay Wet.
One of the "cornerstones" of our botanical-method aquarium practice is the use of substrate. Specifically, substrate materials which can influence- or make it easier to influence- water chemistry in the aquarium, as well as to help foster a "microbiome" of small organisms which will provide ecological diversity for the system.
Substrates, IMHO, are one of the most often-overlooked components of the aquarium. We tend to just add a bag of "_____________" to our tanks and move on to the "more exciting" stuff like rocks and "designer" wood. It's true! Other than planted aquarium enthusiasts, the vast majority of hobbyists seem to have little more than a passing interest in creating and managing a specialized substrate or associated ecology.
A real pity, especially for those of us who are interested in botanical-method aquariums, which replicate natural aquatic habitats where soils and geology play a HUGE role in influencing the environmental parameters of these ecosystems. And in the hobby, we've largely overlooked the benefits and possibilities which specialized substrates can offer.
So I started to experiment with materials to recreate some of the characteristics of wild aquatic habitats which fascinated me. And an obsession was born.
I started playing with substrates mainly because I couldn't find exactly what I was looking for on the market. This is not some indictment of the major substrate manufacturers out there...I LOVE almost all of them and use and happily recommend ones that I like. I'm obsessed with substrates. I think that the companies which produce them are among the coolest of the cool aquatics industry brands. If I wasn't doing this botanical thing with Tannin, I'd probably have started a company that specializes in substrates for aquariums. Seriously.
And the fact is, the major manufacturers need to market products that more than like 8 people are interested in. It's unreasonable to think that they'd devote precious resources to creating a product that would be geared to such a tiny target.
And of course, being one of those 8 people who are geeked-out about weird substrates, I decided that I'd "scratch my own itch" (as we did with the botanical thing..) and formulate and create some of my own. Thus, the NatureBase product line was born!
I realized that the specialized world which we operate in embraces some different ideas, unusual aesthetics, and is fascinated by the function of the environments we strive to replicate. These are important distinctions between what we are doing with substrates at Tannin, and what the rest of the aquarium hobby is doing.
Our NatureBase line is not intended to supersede or completely replace the more commonly available products out there as your "standard" aquarium substrate, because: a) they're more expensive, b) they're not specifically "aesthetic enhancements", c) they are not intended to be planted aquarium substrates, and d) because of their composition, they'll add some turbidity and tint to the aquarium water, at least initially (not everyone could handle THAT!)
So, right there, those factors have significantly segmented our target market...I mean, we're not trying to be the aquarium world's "standard substrate", they weren't formatted to grow aquatic plants, we're not marketing them just for the cool looks, and we can't emphasize enough that they will make your water a bit turbid when first submerged. If you have fishes which dig, or which like to "work" the substrate, you may see a near-continuous turbidity in your aquarium!
Those factors alone will take us out of contention for large segments of the market!
This is important to grasp.
I mean, these substrates are intended to be used in more natural, botanical-style/biotope-inspired aquariums. Our first two releases, "Igapo" and "Varzea", are specific to the creation of a type of "cyclical" terrestrial/aquatic feature. They do exactly what I wanted them to do, and they were specifically intended for use in specialized set ups, like the "Urban Igapo" idea we've been talking about for a long time here, as well as brackish water mangrove environments, etc.
Let's touch on the "aesthetic" part for a minute.
Most of our NatureBase substrates have a significant percentage of clays and sediments in their formulations. These materials have typically been something that aquarists have avoided, because they will cloud the water for a while, and often impart a bit of color. We also have some botanical components in a few of our substrates, because they are intended to be "terrestrial" substrates for a while before being flooded...and when this stuff is first wetted, some of it will float.
And that means that you're going to have to net it out, or let your filter take it out. You simply won't have that "issue" with your typical bag of aquarium sand!
Shit, you're probably just frothing right now, waiting to cloud and dirty up your aquariums with this stuff, huh?
I can't for the life of me figure out why not? ;)
Remember, some of these substrates were formulated for a very specific purpose: To replicate the terrestrial soils which are seasonally inundated in the wild. As such, these products simply won't look or act like your typical aquarium substrate materials!
Scared off completely yet? I hope not.
Why include sediments and clays in our mixes?
Well, for one thing, sediments are an integral part of the natural substrates in the habitats from which our fishes come. So, they're integral to our line. In fact, I suppose you'd best classify NatureBase products as "sedimented substrates."
Think about this: Many of our favorite habitats are forest floors and meadows which undergo periodic flooding cycles in the Amazon, which results in the creation of aquatic habitats for a remarkable diversity of fish species.
Depending on the type of water that flows from the surrounding rivers, the characteristics of the flooded areas may vary. Another important impact is the geology of the substrates over which the rivers and streams pass. This results in differences in the physical-chemical properties of the water.
In the Amazon, areas flooded by rivers of black or clear waters, with acid pH and low sediment load, in addition to being nutritionally poor, are called “igapó."
The flooding often lasts for several weeks or even several months, and the plants and trees need special biochemical adaptations to be able to survive the lack of oxygen around their roots. We've talked about this a lot here over the years.
Forest floor soils in tropical areas are known by soil geologists as "oxisols", and have varying amounts of clay, sediments, minerals like quartz and silica, and various types of organic matter. So it makes sense that when flooded, these "ingredients" will have significant impact on the aquatic environment. This "recipe" is not only compositionally different than typical "off-the-shelf" aquarium sands and substrates- it looks and functions differently, too.
YOU DON'T RINSE THEM BEFORE USE!
You CAN wet them right away; you don't have to do a "wet/dry season" igapo-style tank with them. However, you should be ready for some cloudy water for a week or more! And again, if you have fishes which like to "work" the substrate, it will be a near-constant thing, the degree to which it will be is based on the habits of the fishes you keep.
And that's where a lot of people will metaphorically "leave the room."Turbid, darker water is a guaranteed "freak out" for a super-high high percentage of aquarists.
So, yeah, you'll have to make a mental shift to appreciate a different look and function.
And many hobbyists simply can't handle that. I've been extremely up front with this stuff since the introduction of these substrates, to ward off the, "I added NatureBase to my tank and it looks like a cloudy mess! This stuff is SHIT!" type of emails that inevitably come when people don't read up first before they purchase the stuff. (And trust me- the fact that you're even reading this blog, or listening to this podcast puts you in the tiniest minority of aquarium hobbyists!)
Let's talk a bit about how to "live" with these substrates.
There are a lot of different ways to use these substrates in all sorts of tanks. I mean, if you want some of the benefits and want to geek out and experiment with them, you can use a "sand cap" of whatever conventional substrate you prefer on top, and likely limit the turbidity somewhat, much like the practice of aquarists who employ "dirted" substrates do.
Oh, and the plant thing...
We're asked a LOT if these substrates can grow aquatic plants. Now, although they were intended to facilitate the growth of terrestrial plants, like grasses, the fact is, both our customers and ourselves have seen pretty damn good plant growth in tanks using this stuff!
Our Igapo and Varzea substrates mimic sandy acidic soils that have a low nutrient content. And, as you know, the color and acidity of the floodwater is due to the acidic organic humic substances (tannins) that dissolve into it. The acidity from the water translates into acidic soils, which makes sense, right?
Now, I admit, I am NOT a geologist, and I'm not expert in soil science. I know enough to realize that, in order to replicate the types of habitats I am fascinated with, it required different materials. If you ask me, "Will this fish do well with this materials?" or, "Can I grow "Cryptocoryne in this?", or "Does this make a good substrate for shrimp tanks?" I likely won't have a perfect answer. Sorry.
Periodically, plant enthusiasts will ask me about the "cation exchange capacity" of our substrate. Cation Exchange Capacity (CEC) is the ability of a material to absorb positively-charged nutrient ions. This means the substrate will hold nutrients and make them available for the plant roots, and therefore, plant growth. CEC measures the amount of nutrients, more specifically, positivity changed ions, which a substrate can hold onto/store for future use by aquatic plants.
Thus, a "high CEC" is important to many aquatic plant enthusiasts in their work. While it means that the substrate will hold nutrients and make them available for the plant roots. it doesn't indicate the amount of nutrients the substrate contains.
For reference, scientists measure cation exchange capacity (CEC) in milliequivalents per 100 grams ( meq/100g).
To really get "down and dirty" to analyze substrates scientifically, CEC determinations are often done by a process called "Method 9081A of EPA SW- 846." What the....? CEC extractions are often also analyzed on ICP-OES systems. A rather difficult and pretty expensive process, with equipment and methods that are not something casual hobbyists can easily replicate!
As you might suspect, CEC varies widely among different materials. Sand, for instance, has a CEC less than 1 meq/100 g. Clays tend to be over 30 meq/100 g. Stuff like natural zeolites are around 100 meq/100g! Soils and humus may have CEC up to 250 meq/100g- that's pretty serious!
What nutrients are we talking about here? The most common ones which come into play in the context of CEC are iron, potassium, calcium and magnesium. So, if you're into aquatic plants, high CEC is a good thing!
Of course, this is where the questions arise around the substrates we play with.
It makes sense, right?
Our "Nature Base" substrates do contain materials such as clays and silts, which could arguably be considered "higher CEC" materials, because they're really fine- and because higher surface area generally results in a higher CEC. The more surface area there is, the more potential bonding sites there are for the exchange to take place. Alas, nothing is ever exactly what we hope it should be in this hobby, and clays are often not all that high in their CEC "ratings."
Now, the "Nature Base" substrates are what we like to call “sedimented substrates”, because they are not just sand, or pellets of fired clays, etc. They are a mix of materials, and DO also have some terrestrial soils in the mix, too, which are also likely higher in CEC. And no, we haven't done CEC testing with our substrates...It's likely that in the future, some enthusiastic and curious scientist/hobbyist might just do that, of course!
Promising, from a CEC standpoint, I suppose!
However, again, I must emphasize that they were really created to replicate the substrate materials found in the igapo and varzea habitats of South America, and the overall habitat- more "holistically conceived"-not specifically for plant growth. And, in terrestrial environments like the seasonally-inundated igapo and varzea, nutrients are often lost to volatilization, leaching, erosion, and runoff..
So, it's important for me to make it clear again that these substrates are more representative of a terrestrial soil. Interestingly, the decomposition of detritus and leaves and such in our botanical-method aquariums and "Urban Igapo" displays is likely an even larger source of “stored” nutrients than the CEC of the substrate itself, IMHO. Thus, they will provide a home for beneficial bacteria- breaking down organics and helping to make them more available for plant growth.
Perhaps that's why aquatic plants grow so well in botanical-method aquariums?
Yeah, the stuff DOES grow aquatic and riparian plants and grasses quite well, in our experience! Yet, again- I would not refer to them specifically as "aquatic plant substrates." They're not being released to challenge or replace the well-established aquatic plant soils out there. They're not even intended to be compared to them!
Remember, our "Igapo" and "Varzea" substrates are intended to start out life as "terrestrial" materials, gradually being inundated as we bring on the "wet season." And because of the clay and sediment content of these substrates, you'll see some turbidity or cloudiness in the water. It won't immediately be crystal-clear- just like in Nature. That won't excite a typically planted aquarium lover, for sure.
I can't stress it often enough: With our emphasis on the "wholistic" application of our substrate, our focus is on the "big picture" of these closed aquatic ecosystems.
I'll be the first to tell you that, while I have experimented with many species of plants, inverts, and fishes with these substrates, I can't tell you that every single fish or plant will like them. You'll simply have to experiment!
Well, shit- that's not something that you typically hear an aquarium hobby brand tell you to do with their products every day, huh? Like, I'm not going to make all sorts of generalized statements about everything I think that these products can do. It would be very unhelpful. I'd rather focus on how they perform in the types of systems in which they were intended to work in, and what the possible downsides could be!
The whole point here is that these substrates are perfect for a whole range of applications. They're not "the greatest substrates ever made!" or anything like that. However, they are super useful for replicating the soils of some of our favorite aquatic habitats.
And for doing some of those geeky experiments that we love so much. So, that pretty much covers the "sedimented" substrate thing for now. Let's talk about "alternative" substrates for a bit...
PT.2 : "ALTERNATIVE SUBSTRATES" AND THE "DANGERS" FROM WITHIN?
In my experience, and in the reported experiences from hundreds of aquarists who play with botanical materials breaking down in and on their aquariums' substrates, undetectable nitrate and phosphate levels are typical for this kind of system. When combined with good overall husbandry, it makes for incredibly stable systems.
I've been thinking through further refinements of the "deep botanical bed"/sand substrate relationship. I've been spending a lot of time researching natural aquatic systems and contemplating how we can translate some of this stuff into our closed system aquaria.
Now, I realize, when contemplating really deep aggregations of substrate materials in the aquarium, that we're dealing with closed systems, and the dynamics which affect them are way different than those in Nature, for the most part.
And I realize that experimenting with these unusual approaches to substrates requires not only a sense of adventure, a direction, and some discipline- but a willingness to accept and deal with an entirely different aesthetic than what we know and love. And this also includes pushing into areas and ideas which might make us uncomfortable, not just for the way they look, but for what we are told might be possible risks.
One of the things that many hobbyists ponder when we contemplate creating deep, botanical-heavy substrates, consisting of leaves, sand, and other botanical materials is the possible buildup of hydrogen sulfide, CO2, and other undesirable compounds within the substrate.
Well, it does make sense that if you have a large amount of decomposing material in an aquarium, that some of these compounds are going to accumulate in heavily-"active" substrates. Now, the big "bogeyman" that we all seem to zero in on in our "sum of all fears" scenarios is hydrogen sulfide, which results from bacterial breakdown of organic matter in the total absence of oxygen.
Let's think about this for just a second.
In a botanical bed with materials placed on the substrate, or loosely mixed into the top layers, will it all "pack down" enough to the point where there is a complete lack of oxygen and we develop a significant amount of this reviled compound in our tanks? I just don't think so. I think that we're more likely to see some oxygen in this layer of materials, and I can't help but speculate- and yeah, it IS just speculation- that actual de-nitirifcation (nitrate reduction), which lowers nitrates while producing free nitrogen, might actually be able to occur in a "(deep) botanical" bed.
And it's certainly possible to have denitrification without dangerous hydrogen sulfide levels. As long as even very small amounts of oxygen and nitrates can penetrate into the substrate, this will not become an issue for most systems. I personally have yet to see a botanical-method aquarium where the material has become so "compacted" as to appear to have no circulation whatsoever within the botanical layer.
Now, sure, I'm not a scientist, and I base this on the management of, and close visual inspection of numerous aquariums, as well as the basic chemical tests I've run on my systems under a variety of circumstances. As one who has made it a point to keep my botanical-method aquariums in operation for very extended time frames, I think this is significant. The "bad" side effects we're talking about should manifest over these longer time frames...and they just haven't.
And then there's the question of nitrate.
Although not the terror that ammonia and nitrite are known to be, nitrate accumulation is something a lot of hobbyists are concerned with. As nitrate accumulates, fish will eventually suffer some health issues. Ideally, we strive to keep our nitrate levels no higher than 5-10ppm in our aquariums.
As a reef aquarist, I was always of the "...keep it as close to zero as possible." mindset, until I realized that corals just grow better with the presence of some nitrate! This was especially evident in my large scale coral grow-out raceways.
It seems that 'zero" nitrate is not always the most realistic or achievable target in a heavily-botanical-laden aquarium, although I routinely see undetectable nitrate reading in my tanks. You have a bit more "wiggle room", IMHO, however, before concern over fish health is a factor. Now, when you start creeping towards 50ppm, you're getting closer towards a number that should alert you.
It's not a big "stretch" from 50ppm to more potentially detrimental readings of 75ppm and higher...
And then you get towards the range where health issues could manifest themselves in your fishes. Now, many fishes will not show any symptoms of nitrate poisoning until the nitrate level reaches 100 ppm or more. However, studies have shown that long-term exposure to moderate concentrations of nitrate stresses fishes, making them more susceptible to disease, affecting their growth rates, and inhibiting spawning in many species.
At those really high nitrate levels, fishes will become noticeably lethargic, and may have other health issues that are obvious upon visual inspection, such as open sores or reddish patches on their skin. And then, you'd have those "mysterious deaths" and the sudden death (essentially from shock) of newly-added fishes to the aquarium, because they're not acclimated to the higher nitrate concentrations.
Okay, that's scary stuff. However, high nitrate concentrations are not only manageable- they're something that's completely avoidable in our aquairums.
Quite honestly, even in the most heavily-botanical-laden systems I've played with, I have personally never seen a higher nitrate reading than around 5ppm. Often, as I mentioned above, they're undetectibIe on hobby-level test kits. I attribute this to common sense stuff: Good quality source water (RO/DI), careful stocking, feeding, good circulation, not disturbing the substrate, and consistent basic aquarium husbandry practices (water exchanges, filter maintenance, etc.).
Now, that's just me.
I'm no scientist, certainly not a chemist, but I have a basic understanding of maintaining a healthy nitrogen cycle in the aquarium. And I am habitual-perhaps even obsessive- about consistent maintenance. Water exchanges are not a "when I get around to it" thing in my aquarium management "playbook"- they're "baked in" to my practice.
So yeah, although nitrate is something to be aware of in botanical-method aquariums, it's simply not an ominous cloud hanging over our success.
Relatively shallow sand or substrate beds seem to be optimal for denitrification, and many of us employ them for the aesthetics as well. Light "stirring" of the top layers, if you're concerned about any potential "dead spots" is something that is permissible, IMHO. Any debris stirred up can easily be removed mechanically by filtration, as mentioned above.
But that's it.
Of course, as we already discussed, you don't have to go crazy siphoning the shit (literally!) out of your sand every week, essentially decimating populations of beneficial microscopic infauna -or interfering with their function- in the process.
What I am starting to feel more and more confident about is postulating that some form of denitrification occurs in a system with a layer of leaves and botanicals as a major component of the tank.
Now, I know, I have little rigorous scientific information to back up my theory, other than anecdotal observations and even some assumptions. However, there is always an example to look at- Nature.
Of course, Nature and aquariums differ, one being a closed system and the other being "open." However, they both are beholden to the same laws, aren't they? And I believe that the function of the captive leaf litter bed and the wild litter beds are remarkably similar to a great extent.
The thing that fascinates me is that, in Nature, leaf litter beds perform a similar function; that is, fostering biodiversity, nutrient export, and yes- denitrification. Let's take a little look at a some information I gleaned from the study of a natural leaf litter bed for some insights.
In a slow-flowing wild Amazonian stream with a very deep leaf litter bed, observations were made which are of some interest to us. First off, oxygen saturation was 6.7 3 mg/L (about 85% of saturation), conductivity was 13.8 microsemions, and pH was 3.5.
Some of these parameters (specifically the very low pH) are likely difficult to obtain and maintain in the aquarium, but the interesting thing is that these parameters were stable throughout a months-long investigation.
Oxygen saturation was surpassingly low, given the fact that there was some water movement and turbulence when the study was conducted. The researchers postulated that the reduction in oxygen saturation presumably reflects respiratory consumption by the organisms residing in the litter, as well as low photosynthetic generation (which makes sense, because there is no real algae or plant growth in the litter beds).
And of course, such numbers are consistent with the presence of a lot of life in the litter beds.
Microscopic investigation confirmed that the leaf litter was heavily populated with fungi and other microfauna. There was also a significant amount of fish life. Interestingly, the fish population was largely found in the top 12"/30cm of the litter bed, which was estimated to be about 18"/45cm deep. The food web in this type of habitat is comprised largely of fungal and bacterial growth which occurs in the decomposing leaf litter.
Okay, I"m throwing a lot of information here, and doing what I hope is a slightly better-than-mediocre attempt at tying it all together. The principal assertions I'm making are that, in the wild, the leaf litter bed is a very productive place, and has a significant impact on its surroundings, and that it's increasingly obvious to me that many of the same functions occur in an aquarium utilizing leaf litter and botanicals.
"Enriching" a substrate with botanicals, or composing an entire substrate of botanicals and leaves is a very interesting and compelling subject for investigation by hobbyists.
So, three areas of potential investigation for us:
*Use of botanicals and leaves to comprise a "bed" for bacterial growth and denitrification.
*Understanding the chemical/physical impact of the botanical "bed" on an aquarium. (ie, pH, conductivity, etc.)
*Utilization of a botanical bed to create a supplemental food source for the resident fishes.
We've also touched on the idea of a leaf litter/botanical bed as "nursery" for fry, something more and more hobbyists/breeders are confirming is a logical "go-to" thing for them.
Interesting semi-anecdotal observations from my friends in the know suggest that the biofilms for decaying leaves form a valuable secondary food for the fry of fishes such as Discus, Uaru, (after they’re done feeding on their parent’s exuded slime coat) and even Loricariid catfishes. And I've seen juvenile fishes of a variety of species "appear" from my botanical-rich aquariums over the years, fat and happy, apparently deriving some nutrition from the fungi, bacteria, and small crustaceans which live in, on, and among the leaf litter bed.
My own experience with creating leaf-litter-bed-focused aquariums has proven that supplemental food production for the resident fishes is a real "thing" that we need to consider. It's a valid and very exciting approach to creating a functional closed aquatic ecosystem.
We talk about the concept of "substrate enhancement" or "enrichment" a lot in the context of aquatic botanicals (we tend to use the two terms interchangeably).
Again, we're not talking about "enrichment" in the same context as say, planted aquarium guys, with materials put into the substrate specifically for the benefit of plants. However, the addition of botanical and other materials CAN create a sort of organic "mulch" which benefits many aquatic plants!
Rather, "enrichment" in our context refers to the addition of botanical materials for creating a more natural-appearing, natural-functioning substrate- one which provides a haven for microbial life, as well as for small crustaceans, biofilms, and even algae, to serve as a foraging area for our fishes and invertebrates.
We've found over the years of playing with botanical materials that substrates can be really dynamic places, and benefit from the addition of leaves and other materials. For many years, substrates in aquarium were really just sands and gravels. With the popularity of planted aquariums, new materials, like soils and mineral additives, entered into the fray.
With the botanical-method aquarium starting to gain in popularity, now you're seeing all sorts of materials added on and in the substrate...for different reasons of course.
I think the big takeaway is that we should not be afraid to experiment with the idea of mixing various botanical materials into our substrates, particularly if we continue to embrace solid aquarium husbandry practices.
In my opinion, richer, botanically-enhanced substrate provides greater biological diversity and stability for the closed system aquarium.
Is it for everyone?
Not for those not willing to experiment and be diligent about monitoring and maintaining water quality. Not for those who are superficially interested, or just in it for the unique aesthetics it affords.
However, for those of you who are adventurous, experimental, diligent, and otherwise engaged with managing and observing your aquariums, I think it offers amazing possibilities. Not only will you gain some fascinating insights and the benefits of "on-board" nutrient export/environmental "enrichment"- you will also get the aesthetics of a more natural-looking substrate as well.
Like so many things we do in our niche, the "weird" alternative and botanical-enriched substrate approaches are fascinating, dynamic, and potentially ground-breaking for the aquarium hobby. For the adventurous, diligent, and observant aquarist, they present numerous opportunities to learn, explore, and create amazing, function-first aquatic ecosystems.
Stay creative. Stay observant. Stay diligent. Stay thoughtful...
And Stay Wet.
It goes without saying that the single most important component of our aquariums is also the most obvious...water! As the literal bearer of life and the environment in which our fishes, plants, and other organisms thrive, it's fundamental. it's the reason we're drawn to fishes, not gerbils, Tarantula, or Mice- or whatever other pets people keep!
Yeah, we're into water!
And I dear say that we take it for granted a bit.
Now, sure, some hobbyist rightfully place the importance of good quality, properly-conditioned water at the very top of their "want list" of "Stuff" required for successful aquariums. These are often fish breeders and very serious hobbyists, who understand the fundamental importance of good water for their work.
Some of the most common questions we receive lately are "How much _______ do I need to get my water to look like________?" or "How much_______ is needed to lower the pH in my tank?" Or, "How much do I need to get a good amount of humic substances and tannins into my aquarium?"
I usually respond with a simple, "I don't know."
These are all really good questions. Logical. Important. I kind of feel like many hobbyists are looking for a plug-and-play "formula" or "recipe" for how to accomplish certain water-conditioning tasks.
I totally get that. But the reality is...there IS no "recipe" for how to do this stuff.
And it sucks, I know.
"Why, Scott? I read that you can just add some of this blackwater extract that you can buy online, and maybe add some catappa leaves, and..."
Stop. STOP. Please, we're just making this painful.
Simply adding leaves or bottled extracts to your tap water isn't going to result in "Instant Amazon" or whatever. There are numerous complexities and nuances which contribute to these habitats that to simply recommend adding "X" to your water isn't the whole story.
There are so many variables in the equation that it's almost impossible to give a definitive answer. And yeah, us guys in the botanical biz haven't really helped the situation. Over the years, vendors who sold catappa leaves, for example, would recommend starting amounts ("three leaves per 15 liters of water" or whatever...) of botanical materials to use in aquariums.
I mean, we've sort of done it, too...And, although our recommended "dosage" of leaves was given for different reasons (to avoid adding too much material to your tank too quickly), the idea of a "recipe" in general is kind of delusional, IMHO.
Now, this was all well and good, but it's based on....what? I mean, is this based on how many leaves of _______ size that a typical hobbyist with a 10-gallon aquarium needs to get the water "looking brown?" Or to lower tap water with a starting pH of 7.4 and a KH of ___ to pH of 6.9? Or to impart "x" ppm of tannins or humic substances into this given quantity of water?
See? Add to this story the fact that you really can't soften water and make it more "malleable" by using botanicals or extracts alone, and you've got a good case for confusion! It's just not that simple.
Maybe we can gain a bit of understanding- or at least, an appreciation for the dynamics of this process, by looking once again to Nature.
Have you very thought about how water reaches all of the wild aquatic systems of the world? I mean, it's got to get there some way, right? So, how does it reach the ponds, lakes, streams, and rivers and forest floors of the world?
Well, some simply falls into the body of water directly from the sky, and that's that. Some is a result of other overflowing streams and rivers (like, ya' know- those flooded Igapo forests we talk about!). Inputs of precipitation falling over the area of an aquatic habitat are transferred to the habitat via a number of different pathways.
It's surprisingly complicated.
There's like a whole field of science devoted to studying this process! It's called Hydrology, and it's incredibly interesting...As fish geeks, we're probably already acquainted with this field of study, at least tangentially!
So, water comes from a variety of sources, reaching a myriad of ecological niches. However, not all of the water has such an easy journey on its way into our favorite aquatic habitat!
Even in the case of rainwater, some of it simply lands on tree leaves in the surrounding area and evaporates. This is a process scientists call "interception", and accounts for the fact that not all water makes it to the ground. Water that does reach the ground enters the soil through a process called infiltration. slowly percolating down to soil areas known as the "saturated zone"- and as you'd imagine, this is where the fun really begins! (to a soil geologist, at least!)
The soil properties control the infiltration capacity; these include things like soil permeability, the presence of vegetation and plant roots, and how much water is already in the soil. Through what is known as "ground water flow", ultimately, the water finds it way into our favorite aquatic habitats. It's important to note that soil texture ( the relative proportion of sand, silt and clay particles within the mix) affects infiltration rates.
Sandy soils like the "podzols", common to forested areas of South America that we've talked about have higher permeability than some clay-based soils. In some really arid areas a "crust" can form on the soil surface, decreasing the permeability. And of course, the thickness of the soil directly affects how much water the soil can actually absorb.
And, in many cases, the substrate composition and its relationship with water has direct impact on the life forms which inhabit these aquatic systems. In the case of some habitats, like vernal pools, which are filled with water seasonally, the substrate is of critical importance to the aquatic life forms which reside there.
Yeah, soils and geology are perhaps the primary driver of water composition in Nature.
Let's talk more about "blackwater."
In a blackwater environment, the color is a visual indicator of an influx of dissolved materials that contribute to the "richness" of the environment. Indeed, a blackwater environment is typically described as an aquatic system in which vegetation decays, creating tannins that leach into the water, making a transparent, acidic water that is darkly stained, resembling tea.
But, that's not the whole story, really.
It’s important to really try to understand the most simple of questions- like, what exactly is “blackwater”, anyways?
A scientist or ecologist will tell you that blackwater is created by draining from older rocks and soils (in Amazonia, look up the “Guyana Shield”), which result in dissolved fulvic and humic substances, present small amounts of suspended sediment, and characterized by lower pH (4.0 to 6.0) and dissolved elements, yet higher SiO2 contents. Magnesium, Sodium, Potassium, and Calcium concentrations are typically very low in blackwater. Electrical conductivity (ORP) is also lower than in so-called "whitewater" habitats.
Tannins are also imparted into the water by leaves and other botanical materials which accumulate in these habitats.
The action of water upon fallen leaves and other botanical-derived materials leaches various compounds out of them, creating the deep tint that many of us are so familiar with. Indeed, this "leaching" process is analogous to boiling leaves for tea. The leached compounds are both organic and inorganic, and include things like tannin, carbohydrates, organic acids, pectic compounds, minerals, growth hormones, alkaloids, and phenolic compounds.
Most of the of the extractable substances in the surface litter layer are humic acids, typically coming from decaying plant material. Scientists have concluded that greater input of plant litter leads to greater input of humic substances into ground water.
In other words, those leaves that accumulate on the substrate are putting out significant amounts of humic acids, as we've talked about previously! And although humic substances, like fulvic acid, are found in both blackwater and clear water habitats, the organic detritus (you know, from leaves and such) in blackwater contains more extractable fulvic acid than in clearwater habitats, as one might suspect!
The Rio Negro, for example, contains mostly humic acids, indicating that suspended sediment selectively adsorbs humic acids from black water. The low concentration of suspended sediments in rivers like the Rio Negro is one of the main reasons why high concentrations of humic acids are maintained. With little to no suspended sediment, there is no "adsorbent surface" (other than the substrate of the river, upon which these acids can be taken hold of (adsorb).
When you think about it, all of this this kind of contributes to why blackwater has the color that it does, too. Blackwater in the Amazon basin is colored reddish-brown. Why? Well, it has those organic compounds dissolved in it, of course. And most light absorbtion is in the blue region of the spectrum, and the water is almost transparent to red light, which explains the red coloration of the water!
And many of those organic compounds come from the surrounding land, as touched on above...
In summary, natural "blackwaters" typically arise from highly leached (tropical) environments where most of the soluble elements in the surrounding rocks and soils are rapidly removed by heavy rainfall. Materials such as soils are the primary influence on the composition of blackwater.
Leaves and other materials contribute to the process and appearance in Nature, but are NOT the primary “drivers” of its creation and composition.
So, right from the start, it’s evident that natural blackwater is “all about the soils…” Yeah, I'll repeat it again: It’s more a product of geology than just about anything else.
More confusing, recent studies have found that most of the acidity in black waters can be attributed to dissolved organic substances, and not to dissolved carbonic acid. In other words, organic acids from compounds found in soil and decomposing plant material, as opposed to inorganic sources. Blackwaters are almost always characterized by high percentages of organic acids.
Despite the appearance, as a general rule, blackwater rivers are lower in nutrients than clear rivers. Wouldn't it be interesting, when contemplating more natural biotope/biotype aquariums, to study and take into consideration the surrounding geology and physical characteristics of the habitat? Too recreate the habitat based on the soil or geological composition of the surrounding terrestrial environment?
As we know now, the influence of factors like soil, and the presence of terrestrial materials like seed pods, leaves, and branches play a huge role in the chemical composition and appearance-of the water. It's really no different in the aquarium, right?
Like so many things in nature, the complexity of blackwater habitats is more than what meets the eye. Chemically, biologically, and ecologically, blackwater habitats are a weave of interdependencies- with soil, water, and surrounding forest all functioning together to influence the lives of the fishes which reside within them. No single factor could provide all of the necessary components for fish populations to thrive.
To damage or destroy any one of them could spell disaster for the fishes- and the ecosystem which supports them. It is therefore incumbent upon us to understand, protect, and cherish these precious habitats, for the benefit of future generations.
And with regards to our aquarium work?
Although there may even be breakthroughs in terms of blackwater extracts and additives coming to market, there are still a lot of questions that would have to be answered before we could simply state that "X" drops per gallon of such an such a formula would yield a specific outcome. This reminds me of the reef aquarium world more an more, lol.
So, if I've made any "argument" here, it's that this stuff is every bit as much of an "art"- in terms of aquarium keeping- as it is a "science." We will, at least for the foreseeable future, have to use the data we have available and formulate a best guess as to how much of what can give us some of the impacts we are interested in for our aquariums.
We simply can't authoritatively make blanket statements like, "You need to use "X" catappa leaves per gallon in order to recreate Rio Negro-like conditions in your aquarium!" We can't simply state that you can throw in some podzolic soil and achieve blackwater, either. There are many factors in play, as we've discussed here, right?
Marketing hyperbole aside, we really are sort of...guessing.
And that's certainly nothing to be discouraged about!
We, as a community, are getting deeper into the functional aspects of blackwater, botanical-style aquariums than ever before. More light is being shed on what's going on in both our aquariums and in the natural habitats we desire to replicate. We are learning more every day about how the presence of tannins and humic substances in our aquariums is affecting the health, longevity, and spawning behaviors of our blackwater fishes.
We're learning about the challenges and realities of managing blackwater systems over the long term- understanding the good, the bad, and the dangerous possibilities that are present when we experiment with these ideas.
There is much, much more work to be done..And a lot of talented hobbyists like yourself are out there on the front lines every day, contributing to the body of knowledge that will benefit the hobby for generations!
Stay persistent. Stay bold. Stay open-minded. Stay curious. Stay disciplined...
And Stay Wet.
I've always been fascinated by environments which transform from dry, terrestrial ones to lush aquatic ones during the course of the year. I remember as a kid visiting a little depression in a field near my home , which, every spring, with the rains would turn into a little pond, complete with frogs, Fairy Shrimp, and other life forms. I used to love exploring it, and was utterly transfixed by the unique and dynamic seasonal transition.
The thrill and fascination of seeing that little depression in the ground, which I later learned was called a "vernal" or "temporal" pool by ecologists, never quite left me. As a fish geek, I knew that one day I'd be able to incorporate what I had seen into my fish keeping hobby...somehow.
About 5 years ago, I got a real "bug up my ass", as they say, about the flooded forests of South America. There is something alluring to me about the way these habitats transition between terrestrial and aquatic at certain times of the year. The migration of fishes and the emergence of aquatic life forms in a formerly terrestrial environment fascinates me- as does the tenacity of the terrestrial organisms which hang on during these periods of inundation.
So, I began playing with aquariums configured to replicate the function and form of these unique habitats. I spent a lot of time studying the components of the Igapo and Varzea environments- the soils, plants, fauna, etc., and learning the influences which lead to their creation and function.
Once I had a grasp of the way these dynamic ecologies work, the task of attempting to recreate them in the aquarium became more realistic and achievable. I realized that, although hobbyists have created what they call "Igapo" simulations in biotope contests for years, for example, it was always a representation of the "wet" season. Essentially a living "diorama" of sorts. Not really a true simulation of the seasonal dynamics which create these habitats.
They were cool, but something was somehow missing to me. With those representations, you throw in some leaves, twigs, and seed pods, maybe a few plants, and call your tank a "flooded forest." I mean, essentially a botanical-style aquairum, although the emphasis was on appearance, not function. That wasn't really that difficult to do, nor much of a advancement in the current state of the art of aquarium keeping. I could do that already. Rather, I wanted to recreate the process- all of it- or as much as possible- in my aquariums.
Thus, the idea of the "Urban Igapo"- a functional representation of a transitional aquatic habitat was born.
The concept behind the "Urban Igapo" is pretty straightforward:
The idea is to replicate to a certain extent, the seasonal inundation of the forests and grasslands of of Amazonia by starting the tank in a 'terrestrial phase", then slowly inundating it with water over a period of weeks or more; then, running the system in an "aquatic phase" for the duration of the 'wet season", then repeating the process again and again.
Because you can do this in the comfort of your own home, we called the concept the "Urban Igapo." About 2 years ago, we went more in depth with some of the procedures and techniques that you'd want to incorporate into your own executions of the idea.
As with so many things in the modern aquarium hobby, there is occasionally some confusion and even misunderstandings about why the hell we do this in the first place!
Well, that's a good question! I mean, the whole idea of this particular approach is to replicate as faithfully as possible the seasonal wet/dry cycles which occur in these habitats. It starts with a dry or terrestrial environment, managed as such for an extended period of time, which is gradually flooded to simulate inundation which occurs when the rainy season commences and swollen rivers and streams overflow into the forest or grassland.
Sure, you can replicate the "wet season" only- absolutely. I've seen tons of tanks created by hobbyists to do this. However, if you want to replicate the seasonal cycle- the real magic of this approach- you'll find as I did that it's more fun to do the "dry season!"
Think of it in the context of what the aquatic environment is- a forest floor or grassland which has been flooded. If you develop the "hardscape" (gulp) for your tank with that it mind, it starts making more sense. What do you find on a forest floor or grassland habitat? Soil, leaf litter, twigs, seed pods, branches, grasses, and plants.
Just add water, right?
Well, sort of.
Now, recently, one of my friends who was presenting his experiences with this approach was just getting pounded on a forum by some, well- let's nicely call them "skeptics"- you know, the typical internet-brave "armchair expert" types- about why you'd do this and how it can't lead to a stable aquarium and how it's "not a blackwater aquarium" (okay, it wasn't presented as such, but it could be...) and that it's just a "dry start" (Well, sort of, but you have to understand the concept behind it, dude), and that you don't need to do it this way and...well- that kind of stuff.
I mean, the full compliment of negative, ignorant, questions by people clearly frightened about someone trying to do something a little differently. In a typical display of online-warrior hypocrisy, one particularly nasty hack did not even bother to research the idea or think about what it was really trying to do before laying into my friend.
Apparently, for these people, there was a lot to unpack.
I mean, first of all, the idea was not intended to be a "dry start" planted tank. It just wasn't. I mean, it starts out "dry", but that's where the similarity ends. This ignorant comment is a classic example of the way some hobbyists make assumptions based on a superficial understanding of something.
We aren't trying to grow aquatic plants here. It's about creating a habitat of terrestrial plants snd grasses, allowing them to establish, snd then inundating the display. Most of the terrestrial grasses will simply not survive extended periods of time submerged. Now, you COULD add adaptable aquatic plants- there are no "rules"- but the intention was to replicate a seasonal dynamic.
The other point, which is utterly lost on some people, is that establishing a "transitional" environment in an aquarium takes time and patience. One dummy literally called the process "complete nonsense" and a "waste of time." This is exactly the kind of self-righteous, ignorant hobbyist who will never get it. In fact, I'm surprised guys like that actually have any success at anything in the hobby.
Such a dismissive and judgmental attitude.
The wet season in The Amazon runs from November to June. And it rains almost every day. And what's really interesting is that the surrounding Amazon rain forest is estimated by some scientists to create as much as 50% of its own precipitation! Think about THAT for a minute. It does this via the humidity present in the forest itself, from the water vapor present on plant leaves- which contributes to the formation of rain clouds.
Yeah, trees in the Amazon release enough moisture through photosynthesis to create low-level clouds and literally generate rain, according to a recent study published in the Proceedings of the National Academy of Sciences (U.S.)!
But it makes a lot of sense, right?
Yet another reason why we need to protect these precious habitats. You cut down a tree in the Amazon- you're literally reducing the amount of rain that can be produced.
It's that simple.
That's really important. It's more than just a cool "cocktail party sound bite."
So what happens to the (aquatic) environment in which our fishes live in when it rains? What does the rain actually do?
Well, for one thing, rain performs the dual function of diluting organics, while transporting more nutrient and materials across the ecosystem. What happens in many of the regions of Amazonia, for example- is the evolution of our most compelling environmental niches. The water levels in the rivers rise significantly. often several meters, and the once dry forest floor fills with water from the torrential rain and overflowing rivers and streams.
The Igapos are formed.
Flooded forest floors.
The formerly terrestrial environment is now transformed into an earthy, twisted, incredibly rich aquatic habitat, which fishes have evolved over eons to live in and utilize for food, protection, and spawning areas.
All of the botanical material-shrubs, grasses, fallen leaves, branches, seed pods, and such, is suddenly submerged; often, currents re-distribute the leaves and seed pods and branches into little pockets and "stands", affecting the (now underwater) "topography" of the landscape.
Leaves begin to accumulate.
Soils dissolve their chemical constituents- tannins, and humic acids- into the water, enriching it. Fungi and micororganisms begin to feed on and break down the materials. Biofilms form, crustaceans multiply rapidly. Fishes are able to find new food sources; new hiding places..new areas to spawn.
So, yeah, the rains have a huge impact on tropical aquatic ecosystems. And it's important to think of the relationship between the terrestrial habitat and the aquatic one when visualizing the possibilities of replicating nature in your aquarium in this context.
It's an intimate, interrelated, "codependent" sort of arrangement!
To replicate this process is really not difficult. The challenging part is to separate what we are trying to do here from our preconceptions about how an aquarium should work. To understand that the resulting aquatic display won't initially look or function like anything that we're already familiar with.
While it superficially resembles the "dry start" method that many aquatic plant enthusiasts play with, it's important to remember that our goal isn't to start plants for a traditional aquarium. It's to establish terrestrial growth and to facilitate a microbiome of organisms which help create this habitat. It's to replicate, on some levels, the year-round dynamic of the Amazonian forests. We favor terrestrial plants- and grasses-grown from seed, to start the "cycle."
So, those of you who are ready to downplay the significance of experimenting with this stuff because "people have done 'dry start' planted tanks for years", take comfort in the fact that I recognize that, and acknowledge that we're taking a slightly different approach here, okay?
You'll need to create a technical means or set of procedures to gradually flood your "rainforest floor" in your tank, which could be accomplished manually, by simply pouring water into the vivarium over a series of days; or automatically, with solenoids controlling valves from a reservoir beneath the setup, or perhaps employing the "rain heads" that frog and herp people use in their systems. This is all very achievable, even for hobbyists like me with limited "DIY" skills.
You just have to innovate, and be willing to do a little busy work. You can keep it incredibly simple, and just utilize a small tank.
You must be patient.
And of course, there are questions. Here are some of the major/common ones we receive about this concept:
Does the grass and plants that you've grown in the "dry season" survive the inundation?
A great question. Some do, some don't. (How's that for concise info!). I've played with grasses which are immersion tolerant, such as Paspalum. This stuff will "hang around" for a while while submerged for about a month and a half to two months, in my experience, before ultimately succumbing. Sometimes it comes back when the "dry season" returns. However, when it doesn't survive, it decomposes in the now aquatic substrate, and adds to the biological diversity by cultivating fungi and bacteria.
You can use many plants which are riparian in nature or capable of growing emmersed, such as my fave, Acorus, as well as all sorts of plants, even aquatics, like Hydrocotyle, Cryptocoryne, and others. These can, of course, survive the transition between aquatic and "terrestrial" environments.
How long does the "dry season" have to last?
Well, if you want to mimic one of these habitats in the most realistic manner possible, follow the exact wet and dry seasons as you'd encounter in the locale you're inspired by. Alternatively, I'd at least go 2 months "dry" to encourage a nice growth of grasses and plants prior to inundation.
And of course, you cans do this over and over again! If you're trying to keep fishes like annual killifishes, the "dry season" could be used on the incubation period of their eggs.
When you flood the tank, doesn't it make a cloudy mess? Does the water quality decline rapidly?
Sure, when you add water to what is essentially a terrestrial "planter box", you're going to get cloudiness, from the sediments and other materials present in the substrate. You will have clumps of grasses or other botanical materials likely floating around for a while.
Surprisingly, in my experience, the water quality stays remarkably good for aquatic life. Now, I'm not saying that it's all pristine and crystal clear; however, if you let things settle out a bit before adding fishes, the water clears up and a surprising amount of life (various microorganisms like Paramecium, bacteria, etc.) emerges.
Curiously, I personally have NOT recorded ammonia or nitrite spikes following the inundation. That being said, you can and should test your water before adding fishes. You can also dose bacterial inoculants, like our own "Culture" or others, into the water to help. The Purple Non-Sulphur bacteria in "Culture" are extremophiles, particularly well adapted to the dynamics of the wet/dry environment.
Should I use a filter in the "wet season?"
You certainly can. I've gone both ways, using a small internal filter or sponge filter in some instances. I've also played with simply using an air stone. Most of the time, I don't use any filtration. I just conduct partial water exchanges like I would with any other tank- although I take care not to disturb the substrate too much if I can. When I scaled up my "Urban Igapo" experiments to larger tanks (greater than 10 gallons), Il incorporated a filters with no issues.
A lot of what we do is simply letting Nature "take Her course."
Ceding a lot of the control to Nature is hard for some to quantify as a "technique" or "method", so I get it. At various phases in the process, our "best practice" might be to simply observe...
And with plant growth slowing down, or even going completely dormant while submerged, the utilization of nutrients via their growth diminishes, and aquatic life forms (biofilms, algae, aquatic plants, and various bacteria, microorganisms, and microcrustaceans) take over. There is obviously an initial "lag time" when this transitional phase occurs- a time when there is the greatest opportunity for one life form or another (algae, bacterial biofilms, etc.) to become the dominant "player" in the microcosm.
It's exactly what happens in Nature during this period, right?
And there are parallels in the management of aquariums.
In our aquarium practice, it's the time when you think about the impact of technique-such as water exchanges, addition of aquatic plants, adding fishes, reducing light intensity and photoperiod, etc. and (again) observation to keep things in balance- at least as much as possible. You'll question yourself...and wonder if you should intervene- and how..
It's about a number of measured moves, any of which could have significant impact- even "take over" the system- if allowed to do so. This is part of the reason why we don't currently recommend playing with the Urban Igapo idea on a large-tank scale just yet. (that, and the fact that we're not going to be geared up to produce thousands of pounds of the various substrates just yet! 😆)
Until you make those mental shifts to accept all of this stuff in one of these small tanks, the idea of replicating this in 40-50, or 100 gallons is something that you may want to hold off on for just a bit.
I mean, if you understand and accept the processes, functions, and aesthetics of this stuff, maybe you wouldwant to "go big" on your first attempt. However, I think you need to try it on a "nano scale" first, to really "acclimate" to the idea.
The idea of accepting Nature as it is makes you extremely humble, because there is a realization at some point that you're more of an "interested observer" than an "active participant." It's a dance. One which we may only have so much control- or even understanding of! That's part of the charm, IMHO.
These habitats are a remarkable "mix" of terrestrial and aquatic elements, processes, and cycles. There is a lot going on. It's not just, "Okay, the water is here- now it's a stream!"
Nope. There is a lot of stuff to consider.
In fact, one of the arguments one could make about these "Urban Igapo" systems is that you may not want to aggressively intervene during the transition, because there is so much going on! Rather, you may simply want toobserve and study the processes and results which occur during this phase. Personally, I've noticed that the "wet season" changes in my UI tanks generally happen slowly, but you will definitely notice them as they occur.
After you've run through two or three complete "seasonal transition cycles" in your "Urban Igapo", you'll either hate the shit out of the idea- or you'll fall completely in love with it, and want to do more and more work in this alluring little sub-sector of the botanical-style aquarium world.
The opportunity to learn more about the unique nuances which occur during the transition from a terrestrial to an aquatic habitat is irresistible to me. Of course, I'm willing to accept all of the stuff with a very open mind. Typically, it results in a fascinating, utterly beautiful, and surprisingly realistic representation of what happens in Nature.
It's also entirely possible to have your "Urban Igapo" turn into an "Urban Algae Farm" if things get out of balance. Yet, it can "recover" from this. Again, even the fact that a system is "out of balance" doesn't mean that it's a failure. After all, the algae is thriving, right? That's a success. Life forms have adapted. A cause to celebrate.
It happens in Nature, too!
So, that's a brief rundown on the dynamics and challenges of the "Urban Igapo" concept. It will be exciting to see how each of us evolves the idea further!
Stay creative. Stay thoughtful. Stay bold. Stay curious...
And Stay Wet.
Of all the fun topics in botanical-style aquarium keeping, few hold my interest as much as substrates.
I imagine the substrate as this magical place which fuels all sorts of processes within our aquariums, and that Nature tends to it in the most effective and judicious manner.
Yeah, I'm a bit of a "substrate romantic", I suppose.😆
Particularly in transitional habitats, like flooded forests, etc. the composition and characteristics of the substrate plays a huge role in the ecology of the aquatic habitat. The presence of a lot of soils, clays, and sediments in these substrates, as opposed to just sand, creates a habitat which provides a lot of opportunity for organisms to thrive.
The substrates are not just "the bottom."
They are diverse harbors of life, ranging from fungal and biofilm mats, to algae, to epiphytic plants. Decomposing leaves, seed pods, and tree branches compose the substrate for a complex web of life which helps the fishes we're so fascinated by to flourish. And, if you look at them objectively and carefully, they are beautiful.
Detritus ("Mulm") located in the sediments is the major source of energy and/or nutrients for many of these dynamic aquatic habitats. The bacteria which perform all the important chemical reactions, such as converting ammonia to nitrite, nitrates to nitrogen, releasing bound-up nutrients, neutralizing hydrogen sulfide, etc. will obtain essential nutrients from the detritus (this is what autotrophic bacteria that metabolize ammonia/ammonium or hydrogen sulfide for energy do).
These bacteria may also "harvest" those nutrients, as well as metabolize (aerobically or anaerobically) the organic compounds present in the detritus for energy, just like heterotrophs do.
The processing of nutrients in the aquarium is a fascinating one; a real "partnership" between a wide variety of aquatic organisms.
Yes, there is a lot of amazing biological function occurring in these layers. And of course, fostering this dynamic in the aquarium is one of the things we love the most. It's all part of our vision for the modern, botanical-style aquarium.
Now, hobbyists have played with deep sand beds and mixes of various materials in aquariums for many years, and knowledgable proponents of natural aquarium management, such as Diane Walstad, have discussed the merits of such features in far more detail, and with a competency that I could only dream of! That being said, I think the time has never been better to experiment with this stuff!
Again, we're talking about utilizing a wider variety of materials than just sand, so the dynamics are quite different, offering unique functions, processes, and potential benefits.
I've been thinking through further refinements of the "deep botanical bed"/sand substrate relationship. I've been spending a lot of time over the years researching natural aquatic systems and contemplating how we can translate some of this stuff into our closed system aquaria.
Before we talk about the actual substrate materials again, let's think about the processes that we would like to foster in a substrate, and the potential negatives that may be of concern to those of us who play with botanicals in our substrate configurations
One of the things that many hobbyists ponder when we contemplate creating deep, botanical-heavy substrates, consisting of leaves, sand, and other botanical materials is the buildup of hydrogen sulfide, CO2, and other undesirable compounds within the substrate.
Well, it does make sense that if you have a large amount of decomposing material in an aquarium, that some of these compounds are going to accumulate in heavily-"active" substrates. Now, the big "bogeyman" that we all seem to zero in on in our "sum of all fears" scenarios is hydrogen sulfide, which results from bacterial breakdown of organic matter in the total absence of oxygen.
Let's think about this for just a second.
In a botanical bed with materials placed on the substrate, or loosely mixed into the top layers, will it all "pack down" enough to the point where there is a complete lack of oxygen and we develop a significant amount of this reviled compound in our tanks? I think that we're more likely to see some oxygen in this layer of materials, and I can't help but speculate- and yeah, it IS just speculation- that actual de-nitirifcation (nitrate reduction), which lowers nitrates while producing free nitrogen, might actually be able to occur in a "deep botanical" bed.
And it's certainly possible to have denitrification without dangerous hydrogen sulfide levels. As long as even very small amounts of oxygen and nitrates can penetrate into the substrate, this will not become an issue for most systems. I have yet to see a botanical-style aquarium where the material has become so "compacted" as to appear to have no circulation whatsoever within the botanical layer.
Now, sure, I'm not a scientist, and I base this on close visual inspection of numerous aquariums, and the basic chemical tests I've run on my systems under a variety of circumstances. As one who has made it a point to keep my botanical-style aquariums in operation for very extended time frames, I think this is significant. The "bad" side effects we're talking about should manifest over these longer time frames...and they just haven't.
We need to look at substrates literally as an aquatic organism. And, like aggregations of organisms, they may be diverse, both morphologically and ecologically. They're a dynamic, functional part of the miniature ecosystems we create in our aquariums. We've used the "basic" stuff for a generation. It's time to open up our minds to a few new ideas. To rethink substrate. To reconsider why we incorporate substrate, and what we use.
What kinds of materials can we employ to create more "functional" substrates (which just happen to look cool, too?). What kinds of functions and benefits can we hope to recreate in the confines of our aquariums?
First off, think beyond just sands...or anything resembling "conventional" aquarium substrate. Think about what goes on in the benthic (bottom) regions in the natural habitats we love, and what benefits or support the materials which aggregate there provide for the organisms within the ecosystem.
Understand that the substrate is a dynamic, extremely important part of the aquarium, too. And what we construct our substrate with, and how we manage it, is of profound importance to our fishes!
Fostering fungal growth, as well as other microorganisms and small crustaceans, should be a huge component of the "why" we do this. These organisms, as we've discussed repeatedly, form a part of the "food chain" within our captive ecosystems, and offer huge benefits to the aquarium not only as potential supplemental nutrition for fishes, but as a means to process and export nutrients from within the botanical-style aquarium.
So, yeah, in summary- the substrate plays a huge role in the function of a botanical-style aquarium. We can create a "facility" with substrate materials which provides not only unique aesthetics- it provides priceless benefits: Production of supplemental nutrition for our fishes, and nutrient processing via a self-generating population of creatures that compliment, indeed, create the biodiversity in our systems on a more-or-less continuous basis.
True "functional aesthetics!"
A combination of finely crushed leaves, bits of botanicals, small twigs, etc. can form the basis for a more "biologically active" and even productive substrate. As these materials break down, they are colonized by fungi and biofilms, and impart tannins, lignin, and other sources of carbon into the water to fuel a variety of microbial growth.
As you might have gathered by now, we are an advocate of some rather "unconventional" substrate materials, particularly a classification what we call "Sedimented Substrates."
Yeah, that'd be ours. NatureBase "Igapo", "Varzea", and the upcoming "Mangal", "Floresta" and "Selagor", are examples of substrates which have a lot of sediments and clays in their formulation. These substrates realistically replicate the composition, function, and look of soils which are found in many tropical aquatic habitats.
In fact, most of our NatureBase substrates have a significant percentage of clays and sediments in their formulations. These materials have typically been something that aquarists have avoided, because they will cloud the water for a while, and often impart a bit of color. Like, that's a problem? We also have some botanical components in a few of our substrates, because they are intended to be "terrestrial" substrates for a while before being flooded...and when this stuff is first wetted, some of it will float. And that means that you're going to have to net it out, or let your filter take it out.
You simply won't have that "issue" with your typical bag of aquarium sand!
You can mix them with any of the above-mentioned commercially-available sands, or use them alone. You can gradually add water (as in our "Urban Igapo" concept), or simply fill your tank form day one. Expect significant cloudiness for several days as the materials settle out, though. Don't rinse these substrates...just put them to work right away.
Now, although you can (and should) play with these substrates "wet" from the start, I'd be remiss if I didn't remind you again that the igapo and varzea substrates were initially intended to be "terrestrial" for a period of time, to get the grasses and plants going, and then inundated.
So, yeah, you'll have to make a mental shift to appreciate a different look and function. And many hobbyists simply can't handle that. We've been up front with this stuff since these products were released, to ward off the, "I added NatureBase to my tank and it looks like a cloudy mess! This stuff is SHIT!" type of emails that inevitably come when people don't read up first before they purchase the stuff.
And the warning and mental shift indoctrinations have worked. No one has freaked out.
Instead, we're hearing how incredibly natural these aquariums look, and how the biological diversity and stability of these tanks are.
What goes on in an aquarium with sediments, botanicals- or leaves, in this instance as the total "substrate" or "hardscape", as the case may be, is that they become the basis for biological activity in the tank. As we have discussed a million times here, as botanicals break down, they recruit bacteria, fungi, and other organisms on their surfaces.
That's the "big deal" about substrates.
Mix it up. Play with sediments, crushed leaves, broken bits of botanicals..All sorts of natural "stuff" which would previously have been considered "dirty" and "bad for long term maintenance" in almost anyone's book. Look at the advantages that can be realized, instead of the potential risks involved in experimenting.
Open your mind up to accept the look and function- and the "aesthetic challenges" of using non-traditional materials in your substrates.
Stay creative. Stay excited. Stay bold. Stay studious...
And Stay Wet.
One of the things that drives most hobbyists crazy is when "stuff" gets blown around, covered or moved about in the aquarium. It can be because of strong current, the activity of fishes, or simply overgrown by plants. I understand the annoyance that many hobbyists feel; I recall this same aggravating feeling in many reef tanks where I had high flow and sand on the bottom- almost always a combination for annoyance!
I mean, I get it. We have what feel is a carefully thought-out aquascape, looking exactly how we expected it would after setup. Yet, despite our ideas and thoughts, stuff moves around in the aquarium. It's something we can either accept, or modify in our aquariums, depending upon our preferences.
Yet, movement and "covering" of various materials by sediments, biofilms, etc., which accumulate on the substrate in natural habitats are everyday occurrences, and they help forge a very dynamic ecosystem. And they are constantly creating new opportunities for the fishes which reside in them to exploit.
When you think about how materials "get around" in the wild aquatic habitats, there are a few factors which influence both the accumulation and distribution of them. In many topical streams, the water depth and intensity of the flow changes during periods of rain and runoff, creating significant re-distribution of the materials which accumulate on the bottom, such as leaves, branches, seed pods, and the like.
Larger, more "hefty" materials, such as branches, submerged logs, etc., will tend to move less frequently, and in many instances, they'll remain stationary, providing a physical diversion for water as substrate materials accumulate around them.
A "dam", of sorts, if you will.
And this creates known structures within streams in areas like Amazonia, which are known to have existed for many years. Semi-permanent aquatic features within the streams, which influence not only the physical and chemical environment, but the very habits and abundance of the fishes which reside there.
Most of the small stuff, like leaves, tend to move around quite a bit... One might say that the "material changes" created by this movement of materials can have significant implications for fishes. As we've talked about before, they follow the food, often existing in, and subsisting off of what they can find in these areas.
New accumulations of leaves, detritus, and other materials benefit the entire ecosystem.
In the case of our aquariums, this "redistribution" of material can create interesting opportunities to not only switch up the aesthetics of our tanks, but to provide new and unique little physical areas for many of the fishes we keep.
And yeah, the creation of new feeding opportunities for life forms at all levels is a positive which simply cannot be overstated! As hobbyists, we tend to lament changes to the aquascape of our tanks caused by things outside of our control, and consider them to be a huge inconvenience, when in reality, they're not only facsimile of very natural dynamic processes-they are fundamental to their evolution.
The benthic microfauna which our fishes tend to feed on also are affected by this phenomenon, and as mentioned above, the fishes tend to "follow the food", making this a case of the fishes adapting to a changing environment. And perhaps...maybe...the idea of fishes sort of having to constantly adjust to a changing physical environment could be some sort of "trigger", hidden deep in their genetic code, that perhaps stimulates overall health, immunity or spawning?
Something in their "programing" that says, "You're at home..." Perhaps something which triggers specific adaptive behaviors?
I find this possibility fascinating, because we can learn more about our fishes' behaviors, and create really interesting habitats for them simply by adding botanicals to our aquariums and allowing them to "do their own thing"- to break apart as they decompose, move about as we change water or conduct maintenance activities, or add new pieces from time to time.
Again, just like Nature.
We just need to "get over ourselves" on this aesthetic thing!
Another mental shift? Yeah, it is. An easy one, but one that we need make, really.
Like any environment, botanical/ leaf litter beds have their own "rhythm", fostering substantial communities of fishes. The dynamic behind this biotope can best be summarized in this interesting excerpt from an academic paper on blackwater leaf-litter communities by biologist Peter Alan Henderson, that is useful for those of us attempting to replicate these communities in our aquaria:
"..life within the litter is not a crowded, chaotic scramble for space and food. Each species occupies a sub-region defined by physical variables such as flow and oxygen content, water depth, litter depth and particle size…
...this subtle subdivision of space is the key to understanding the maintenance of diversity. While subdivision of time is also evident with, for example, gymnotids hunting by night and cichlids hunting by day, this is only possible when each species has its space within which to hide.”
In other words, different species inhabit different sections of the leaf litter beds. As aquarists, we should consider this when creating and stocking our botanical-style aquariums.
It just makes sense, right?
So, when you're attempting to replicate such an environment, consider how the fishes would utilize each of the materials you're working with. For example, leaf litter areas would be an idea shelter for many juvenile fishes, catfishes, and even young cichlids to shelter among.
Submerged branches, larger seed pods and other botanicals provide territory and areas where fishes can forage for macrophytes (algal growths which occur on the surfaces of these materials). Fish selection can be influenced as much by the materials you're using to 'scape the tank as anything else, when you think about it!
And it's not just fishes, of course. It's a multitude of life forms.
There are numerous life forms which are found on ad among these materials as well, such as fungal growths, bacterial biofilms, etc. which we likely never really consider, yet are found in abundance in nature and in the aquarium, and perform vital roles in the function of the aquatic habitat.
Perhaps most fascinating and rarely discussed in the hobby, are the unique freshwater sponges, from the genus Spongilla. Yes, you heard. Freshwater sponges! These interesting life forms attach themselves to rocks and logs and filter the water for various small aquatic organisms, like bacteria, protozoa, and other minute aquatic life forms. Some are truly incredible looking organisms!
(Spongilla lacustris Image by Kirt Onthank. Used under CC-BY SA 3.0)
Unlike the better-known marine sponges, freshwater sponges are subjected to the more variable environment of rivers and streams, and have adapted a strategy of survival. When conditions deteriorate, the organisms create "buds", known as "gemmules", which are an asexually reproduced mass of cells capable of developing into a new sponge! The Gemmules remain dormant until environmental conditions permit them to develop once again!
To my knowledge, these organisms have never been intentionally collected for aquariums, and I suspect they are a little tricky to transport (despite their adaptability), just ike their marine cousins are. One species, Metania reticulata, is extremely common in the Brazilian Amazon. They are found on rocks, submerged branches, and even tree trunks when these areas are submerged, and remain in a dormant phase in the aforementioned gemmules during periods of desiccation!
Now, I'm not suggesting that we go and collect freshwater sponges for aquarium use, but I am curious if they occur as "hitchhikers" on driftwood, rocks or other materials which end up in our aquariums. When you think about how important sponges are as natural "filters", one can only wonder how they might perform this beneficial role in the aquarium as well!
We've encountered them in reef tanks for many years...I wonder if they could ultimately find their way into our botanical-style aquariums as well? Perhaps they already have. Have any of you encountered one before in your tanks?
The big takeaway from all of this: A botanical bed in our aquariums and in Nature is a physical structure, ephemeral though it may be- which functions just like an aggregation of branches, or a reef, rock piles, or other features would in the wild benthic environment, although perhaps even "looser" and more dynamic.
Stuff gets redistributed, covered, and often breaks down over time. Exactly like what happens in Nature.
Think about the possibilities which are out there, under every leaf. Every sunken branch. Every root. Every rock.
It's all brought about by the dynamic process of movement.
Perhaps instead of looking at the movement of stuff in our tanks as an annoyance, we might enjoy it a lot more if we look at it as an opportunity! An opportunity to learn more about the behaviors and life styles of our fishes and their ever-changing environment.
Stay observant. Stay creative. Stay excited. Stay open-minded...
And Stay Wet.
As you know, we've spent the better part of the past 6 years talking about every aspect of the botanical-style aquarium that we can think of. We've talked about techniques, approaches, ideas, etc. And we've spent a lot of time sharing information about wild aquatic habitats that we might be interested in replicating in both form and function.
However, I think we haven't spent as much time as we should talking about how botanicals "behave" in wild aquatic habitats. Much of this stuff has implications for those of us who are interested in replicating these habitats in our aquariums. So, let's dive in a bit more on this topic today!
Among the trees of the flooded forests, after the fruits mature (which occurs at high water levels), seeds will fall into the water and may float on the surface or be submerged for a number of weeks. Ecologists believe that the seed production of the trees coincides with the flood pulses, which facilitates their dispersal by water movement, and by the actions of fish.
Interestingly, scientists postulate that these floating or sinking seeds, which germinate and establish seedlings after the flood waters recede, do very well, sprouting and establishing themselves quickly, and are not severely affected by waterlogging in most species.
So, within their cycle of life, the trees take advantage of the water as part of their ecological adaptation. Trees in these areas have developed specialized morphologies, such as advantageous roots, butress systems and stilt roots.
In a lot of wild aquatic habitats where leaf litter and other allochthonous materials accumulate, there are a number of factors which control the density, size, and type of materials which are deposited in streams and such. The flow rate of the water within these habitats determines a lot of things, such as the size of the leaves and other botanical materials and where in the stream they are deposited.
I often wonder how much the fallen leaves and seed pods impact the water chemistry in a given stream, pond, or section of an Amazonian flooded forest. I know that studies have been done in which ecologists have measured dissolved oxygen and conductivity, as well as pH. However, those readings only give us so much information.
We hear a lot of discussion about blackwater habitats among hobbyists, and the implications for our aquariums. And part of the game here is understanding what it is that makes this a blackwater river system to begin with. We often hear that blackwater is "low in nutrients."
What exactly does this mean?
One study concluded that the Rio Negro is a blackwater river in large part because the very low nutrient concentrations of the soils that drain into it have arisen as a result of "several cycles of weathering, erosion, and sedimentation." In other words, there's not a whole lot of minerals and nutrients left in the soils to dissolve into the water to any meaningful extent!
Black-waters, drain from older rocks in areas like the Negro river, result from dissolved fulvic and humic substances, present small amounts of suspended sediment, lower pH (4.0 to 6.0) and dissolved elements. Yes, highly leached tropical environments where most of the soluble elements are quickly removed by heavy rainfall.
Perhaps...another reason (besides the previously cited limitation of light penetration) why aquatic plants are rather scare in these waters? It would appear that the bulk of the nutrients found in these blackwaters are likely dissolved into the aquatic environment by decomposing botanical materials, such as leaves, branches, etc.
Why does that sound familiar?
Besides the color, of course, the defining characteristics of blackwater rivers are pH values in the range of 4-5, low electrical conductivity, and minimal mineral content. Dissolved minerals, such as Ca, Mg, K, and Na are negligible. And with these low amounts of dissolved minerals come unique challenges for the animals who reside in these systems.
How do fishes survive and thrive in these rather extreme habitats?
It's long been known that fishes are well adapted to their natural habitats, particularly the more extreme ones. And this was borne out in a recent study of the Cardinal Tetra. Lab results suggest that humic substances protect cardinal tetras in the soft, acidic water in which they resides by preventing excessive sodium loss and stimulating calcium uptake to ensure proper homeostasis.
This is pretty extraordinary, as the humic substances found in the water actually enable the fishes to survive in this highly acidic water which is devoid of much mineral content typically needed for fishes to survive!
And of course, botanicals, leaves, and wood typically have an abundance of these humic substances, right? They are useful for more than just an interesting and unique aesthetic effect! There is a lot of room for research about influencing the overall environment in our aquariums here! I think we've barely scratched the surface of the potential for utilizing botanicals in our aquariums.
This is another one of those foundational aspects of the natural style of aquarium that we espouse. The understanding that processes like decomposition and physical transformation of the materials that we utilize our tanks are normal, expected, and beautiful things requires us to make mental shifts.
Botanical materials don't have nearly as much impact on the water parameters (other than say, conductivity and dissolved oxygen) as the soils do. These waters have high concentrations of humic and fulvic acids derived from sandy "hydromorphic podsols" prevalent in the region. However, these allochthonous materials have huge impact on the ecology of these systems!
Leaf litter, as one might suspect, is of huge importance in these ecosystems. Especially in smaller tributaries. In one study which I came across, it was concluded that, "The smaller the stream, the more dependent the biota is on leaf litter habitats and allocthonous energy derived directly or indirectly from the forest." (Kemenes and Forsberg)
From the same study, it was concluded that the substrate of the aquatic habitat had significant influence on the feeding habits of the fishes which resided in them:
"The biomass of allocthonous insectivore increased in channels with a higher percentage of sandy bottom substrate. Detritivorous insectivore biomass, in contrast, increased significantly in channels with a higher percentage of leaf substrate. General insectivores tended to increase in streams with higher proportions of leafy substrate, too.
Whats the implication for us as hobbyists? Well, for one thing, we can set up the benthic environment in our tanks to represent the appropriate environment for the fishes which we want to keep in them. Simple as that!
t's as much about function as anything else. And, about pushing into some new directions. The unorthodox aesthetics of these unusual aquariums we play with just happen to be an interesting "by-product" of theirfunction.
I personally think that almost every botanical-style aquarium can benefit from the presence of leaves. As we've discussed numerous times, leaves are the "operating system" of many natural habitats (ecology-wise), and perform a similar role in the aquarium.
The presence of botanical materials such as leaves in these aquatic habitats is fundamental. Leaves and other botanicals are extremely pervasive in almost every type of aquatic habitat.
In the tropical species of trees, the leaf drop is important to the surrounding environment. The nutrients are typically bound up in the leaves, so a regular release of leaves by the trees helps replenish the minerals and nutrients which are typically depleted from eons of leaching into the surrounding forests.
Now, interestingly enough, most tropical forest trees are classified as "evergreens", and don't have a specific seasonal leaf drop like the "deciduous" trees than many of us are more familiar with do...Rather, they replace their leaves gradually throughout the year as the leaves age and subsequently fall off the trees.
The implication here?
There is a more-or-less continuous "supply" of leaves falling off into the jungles and waterways in these habitats, which is why you'll see leaves at varying stages of decomposition in tropical streams. It's also why leaf litter banks may be almost "permanent" structures within some of these bodies of water!
Our botanical-style aquariums are not "set-and-forget" systems, and require basic maintenance (water exchanges, regular water testing, filter media replacement/cleaning), like any other aquarium. They do have one unique "requirement" as part of their ongoing maintenance which other types of aquariums seem to nothave: The "topping off" of botanicals as they break down.
The "topping off" of botanicals in your tank accomplishes a number of things: first, it creates a certain degree of environmental continuity- keeping things consistent from a "botanical capacity" standpoint. Over time, you have the opportunity to establish a "baseline" of water parameters, knowing how many of what to add to keep things more-or-less consistent, which could make the regular "topping off" of botanicals a bit more of a "science" in addition to an "art."
In addition, it keeps a consistent aesthetic "vibe" in your aquarium. Consistent, in that you can keep the sort of "look" you have, while making subtle- or even less-than-subtle "enhancements" as desired.
And, of course, "topping off" botanicals helps keeps you more intimately "in touch" with your aquarium, much in the same way a planted tank enthusiast would by trimming plants, or a reefer while making frags. When you're actively involved in the "operation" of your aquarium, you simply notice more. You can also learn more; appreciate the subtle, yet obvious changes which arise on an almost daily basis in our botanical-style aquariums.
I dare say that one of the things I enjoy doing most with my blackwater, botanical-style aquariums (besides just observing them, of course) is to "top off" the botanical supply from time to time. I feel that it not only gives me a sense of "actively participating" in the aquarium- it provides a sense that you're doing something nature has done for eons; something very "primal" and essential. Even the prep process is engaging.
Think about the materials which accumulate in natural aquatic habitats, and how they actually end up in them, and it makes you think about this in a very different context. A more "holistic" context that can make your experience that much more rewarding. Botanicals should be viewed as "consumables" in our hobby- much like activated carbon, filter pads, etc.- they simply don't last indefinitely.
Many seed pods and similar botanicals contain a substance known as lignin. Lignin is defined as a group of organic polymers which are essentially the structural materials which support the tissues of vascular plants. They are common in bark, wood, and yeah- seed pods, providing protection from rotting and structural rigidity.
In other words, they make seed pods kinda tough.
Yet, not permanent.
That being said, they are typically broken down by fungi and bacteria in aquatic environments. Inputs of terrestrial materials like leaf litter and seed pods into aquatic habitats can leach dissolved organic carbon (DOC), rich in lignin and cellulose. Factors like light intensity, mineral hardness, and the composition of the aforementioned bacterial /fungal community all affect the degree to which this material is broken down into its constituent parts in this environment.
Hmm...something we've kind of known for a while, right?
So, lignin is a major component of the "stuff" that's leached into our aquatic environments, along with that other big "player"- tannin.
Tannins, according to chemists, are a group of "astringent biomolecules" that bind to and precipitate proteins and other organic compounds. They're in almost every plant around, and are thought to play a role in protecting the plants from predation and potentially aid in their growth. As you might imagine, they are super-abundant in...leaves. In fact, it's thought that tannins comprise as much as 50% of the dry weight of leaves!
And of course, tannins in leaves, wood, soils, and plant materials tend to be highly water soluble, creating our beloved blackwater as they decompose. As the tannins leach into the water, they create that transparent, yet darkly-stained water we love so much!
In simplified terms, blackwater tends to occur when the rate of "carbon fixation" (photosynthesis) and its partial decay to soluble organic acids exceeds its rate of complete decay to carbon dioxide (oxidation).
Chew on that for a bit...Try to really wrap your head around it...
And sometimes, the research you do on these topics can unlock some interesting tangential information which can be applied to our work in aquairums...
Interesting tidbit of information from science: For those of you weirdos who like using wood, leaves and such in your aquariums, but hate the brown water (yeah, there are a few of you)- you can add baking soda to the water that you soak your wood and such in to accelerate the leaching process, as more alkaline solutions tend to draw out tannic acid from wood than pH neutral or acidic water does. Or you can simply keep using your 8.4 pH tap water!
"ARMCHAIR SPECULATION": This might be a good answer to why some people can't get the super dark tint they want for the long term...If you have more alkaline water, those tannins are more quickly pulled out. So you might get an initial burst, but the color won't last all that long...
I think just having a bit more than a superficial understanding of the way botanicals and other materials interact with the aquatic environment, and how we can embrace and replicate these systems in our own aquariums is really important to the hobby. The real message here is to not be afraid of learning about seemingly complex chemical and biological nuances of blackwater systems, and to apply some of this knowledge to our aquatic practice.
It can seem a bit intimidating at first, perhaps even a bit contrarian to "conventional aquarium practice", but if you force yourself beyond just the basic hobby-oriented material out there on these topics (hint once again: There aren't many!), there is literally a whole world of stuff you can learn about!
It starts by simply looking at Nature as an overall inspiration...
Wondering why the aquatic habitats we're looking at appear the way they do, and what processes create them. And rather than editing out the "undesirable" (by mainstream aquarium hobby standards) elements, we embrace as many of the elements as possible, try to figure out what benefits they bring, and how we can recreate them functionally in our closed aquarium systems.
There are no "flaws" in Nature's work, because Nature doesn't seek to satisfy observers. It seeks to evolve and change and grow. It looks the way it does because it's the sum total of the processes which occur to foster life and evolution.
We as hobbyists need to evolve and change and grow, ourselves.
We need to let go of our long-held beliefs about what truly is considered "beautiful." We need to study and understand the elegant way Nature does things- and just why natural aquatic habitats look the way they do. To look at things in context. To understand what kinds of outside influences, pressures, and threats these habitats face.
And, when we attempt replicate these functions in our aquariums, we're helping to grow this unique segment of the aquarium hobby.
Please make that effort to continue to educate yourself and get really smart about this stuff...And share what you learn on your journey- all of it- the good and the occasional bad. It helps grow the hobby, foster a viable movement, and helps your fellow hobbyists!
Stay studious. Stay thoughtful. Stay inquisitive. Stay creative. Stay engaged...
And Stay Wet.
No brackish water aquarium is complete without brackish-water fishes...And traditionally, that has been a bit of a challenge, in terms of finding some "different" fishes than we've previously associated with brackish aquariums. I think that this will continue to be a bit of a challenge, because some of the fishes that we want are still elusive in the hobby.
New brackish-water fishes will become more readily available when the market demand is there. In the mean time, we can focus on some of the cool fishes from these habitats which are currently available to us.
And there are a few!
They can be hard to find; however, I think the biggest challenge facing those of us who love brackish water aquariums is trying to separate aquarium "fact" from scientific fact! This is pretty fun to do, actually.
However, one of the things I've found is that you need to go beyond "what the hobby articles say" and look into actual information from scientific sources about the types of habitats our target fishes actually come from. There is still a surprisingly large amount of misinformation about there concerning fishes long thought to be "brackish", when the reality is that they are often found predominantly in non-brackish habitats, with perhaps only isolated populations of them being brackish fishes.
Like many hobbyists who play with brackish water tanks, I've found over the years that it's mighty tricky to source genuine brackish water fishes. Through lots of follow up and a bit of luck, I have managed to secure fishes from these types of habitats from time to time, which is, of course, paramount if you're trying to recreate one of these habitats in your aquarium!
As most of you know, I'm no huge cichlid fanatic, but there are some which have found their way into my heart over the decades. One of these is a genuine hobby legend, which just happens to be one of my fave all-time fishes: The venerable "Orange Chromide", Pseudetroplus maculatus - a cichlid with a very weird popular name.
Despite being a cichlid (😆), the Orange Chromide is a relatively easy-going fish that tops out at about 4" in size, which is a huge plus in my book. And, being one of the very few species of cichlids which comes from India, it's even more interesting. In fact, there are just three species which are native to India: Etroplus suratensis, Pseudetroplus maculatus, and the cool and hard-to-find Etroplus canarensis.
Oh, the name. It drives me crazy:
The official Meriam-Webster origin of the name is, "chromide, ultimately from Greek chromis, a sea fish"
A sea fish? WTF?
Yeah, not really satisfying. And it begged me to do little more digging, of course!
But I tried to find out more for you. Now, interestingly, the fish was originally described by the ichthyologist Bloch in 1795 as Chaetodon maculatus...and if this genus sounds familiar to us saltwater aquarium geeks, it should- that's the same genus in which many marine Butterflyfishes are found. And, the fish seems to bear at least a very superficial physical resemblance to a marine Butterflyfish of that genus at first glance...
So, the "Chromide" part of the popular name refers to it's appearance as a "sea fish", or chromis. And, to add a final note of confusion to this taxonomic/popular name scramble, Chromis is a popular genus of colorful marine Damselfishes... So the popular name of this fish is based on it being confusingly similar in appearance to a marine fish... Oh, weird, right?
Yeah, that's why common names are often fraught with problems, and for the ultimate in accuracy, we should at least have a working familiarity with the Latin species names of our fishes. Oh, and this little fish has been bounced around a few genera over the years, from Chaetodon to Etroplus, and finally to Pseudetroplus!
Okay, whatever you call it...This is a pretty interesting fish! Even if it IS a cichlid!😆
And, about that brackish-water thing...
The Orange Chromide endemic to freshwater and brackish streams, lagoons and estuaries in southern India and Sri Lanka. And of course, as soon as we in the hobby hear the word "brackish" when discussing some of the natural habitats in which the fish is found, it forever becomes a brackish water fish!
That's just how it goes in the aquarium hobby, right?
The reality is that the Orange Chromide is classified as a euryhaline fish, and mostly inhabits brackish estuaries, coastal lagoons and the lower reaches of rivers.
Damn, we've heard that term before, haven't we?
That single definition seems to give us as hobbyists the freedom to label the fish as a brackish water fish, despite the fact that it has the ability to live in both pure freshwater and brackish water conditions.
It helps to know exactly where your specimens come from, right?
I was lucky when I sourced my specimens, as there was no ambiguity about what type of habitat they were originally from. Or should I say, where their parents came from. They were actually F1 from parents collected in a brackish water lagoon in the state of Karnataka in western India, so I was pretty happy to be able to keep them in a brackish aquarium and have the confirmation that they were only a generation removed from a natural brackish water habitat.
Okay, all well and good for me, but what if you're not so sure about where your Chromides come from? Well, as we discussed a minute ago, they are euryhaline fishes, and can adapt to brackish relatively easily. You just need to do it very gradually, like over a week or more.
Now, one thing I will tell you about these fishes is that, despite their peaceful reputation, and relatively they can be little shits among themselves. These guys are pretty social...but they also have a social order, which is maintained when feeding and even schooling. The "Alpha male" generally gets to eat first, followed by the less dominant specimens..and of course, he leads the "pack" when they school in the tank (and they do, which is pretty cool!).
And, yeah, the social order in a group of these guys is a big deal. The dominant fish WILL, indeed pick on the weakest ones. In fact, I lost a few over the years due to a super aggressive dominant male essentially bullying and beating the shit out of the subordinate ones in my group before I could remove them.
However, I will tell you to keep them in a group. Not only do they seem to be happier that way, but they display the most interesting behaviors- short of this harassment of the really weak ones. I'd love to tell you that, with a large enough tank, this won't be as big an issue, but I kept mine in a decent-sized tank with lots of hiding spaces and it still was an issue, so...
Another thing about these fishes that you will read is that they are relatively intolerant of poor water quality. Without sounding like an arrogant S.O.B., I'd have to tell you that I won't dispute this, but can't confirm it, because- like most of you- I maintain high water quality in my tanks! It's one of those things that I will just typically accept as a given.
Like many cichlids, spawning is typically a given, given the passage of time and under appropriate environmental conditions. (ie; being in water...)
In the wild, the Orange Chromide spawns in shallow water, typically in a depression in the substrate excavated by both parents. What that tells you, BTW, is that this fish is best kept in a tank with sand, sediment, or other soft substrate materials if you intend to breed them.
It's time to play with dirt, soil, mud, silt, decomposing leaves, branches, marginal plants, roots...materials which replicate both the appearance and function of natural habitats from which many of our fishes come. And, if utilized skillfully and thoughtfully, can yield functionally aesthetic aquariums far different and unique from anything previously attempted in the aquarium hobby. Another call to the evolved, botanical-style brackish-water aquarium!
In Nature, Orange Chromides spawn twice a year, during the drier pre-monsoonal and monsoonal seasons, in which the salinity is slightly higher (an interesting takeaway for us!). During these times, the turbidity of the water is lower, and the parents can more easily construct their nests and maintain visual contact with their fry after they hatch.
Interestingly, in Nature, when Orange Chromide pairs spawn in isolation, they tend to construct nests in areas of dense aquatic vegetation or root systems, which provide a lot of camouflage. Ecologists also have noted that during the month of July, which is their peak breeding season, Chromides will construct their nests in areas that are rather sparsely filled with vegetation, roots, etc.- a sort of compromise between fry survival and foraging opportunities for the adults.
Other, non-spawning fishes will also make use of these areas, increasing the threat to the broods of fry which emerge after hatching. Under these conditions, most Orange Chromides nest in colonies, which is believed to help decrease predation.
Hmm, breeding colonies? Interesting!
About 200 eggs are laid in a typical event, according to just about every source you'll find in the aquarium world. Of course, the largest batch I ever counted was around 100 or so eggs. The eggs hatch after about 5 days, during which time the parents tend to, and fan them.
In typical cichlid fashion, one parent will always remain with the eggs while the other goes out and forages for food. The fry of Orange Chromides feed on the mucus secreted onto the skin of their parents, like Discus or Uaru do. This form of feeding is called "contacting" by biologists. And perhaps most interesting, the good-sized fry are guarded by parents until they almost reach sexual maturity and are almost the size of the parents! Like, a pretty long time! This is a very unique behavior in cichlids!
It is known that immunoglobulin concentrations are higher in the breeding fish than they are in non-breeding ones, and are highest in wild breeding individuals. Biologists are curious to ascertain whether this immunoglobulin is passed on to the contacting fry in the same concentrations as it is found in the mucus. If it is, the big question is how does the increased amount of immunoglobulin affect the growth and survival of these fry?
Want a final bit of unusual trivia on this fish?
Yeah, it's been documented by researchers Richard L. Wyman and Jack A. Ward that the young of Pseudetroplus maculatus actively clean the related species, Etroplus suratensis (the "Green Chromide") when they occur together. .E. suratensis are naturally inhibited from attacking small fish, in case you are wondering!
Much like what you see in the ocean, with Wrasses or Shrimp cleaning territories are established by the young Orange Chromides, and the "shop hours"seem to follow a daily circadian rhythm. This is a unique, almost symbiotic kind of behavior, in which removal of fungus from fins and tail of the E. suratensis appears to be an important adaptive function of this symbiosis.
Interestingly, it's thought by researchers that the "contact feeding" behavior in Orange Chromide fry during parental care may have aided in the evolution of this cleaning relationship. This represents the first report of a cleaning symbiosis involving cichlid fish.
So, yeah, there is much more to this "old hobby favorite" than we might first imagine!
So, what would be some cool ways to keep this fish? Well, to begin with, you should definitely keep them in an aquarium with a fair amount of substrate, roots, and perhaps even a few aquatic plants. Now, if you're aiming to go brackish, it brings up the usual "What plants can grow in brackish water?" discussions...And yeah, there are a few, and you'll need to research that. (Hint: Cryptocoryne ciliata )
Or, you could keep it simple and go for something like a tangled hardscape, with wood and roots, mixed with sand and small quantities of rubble. This would be a very interesting representation of the monsoonal conditions.
Or, you could simply do a "proper" brackish water aquarium with my fave all time plant, the Red Mangrove (Rhizophora mangle). This would be a very rewarding way to keep these fishes, as I can attest!
Yes, new brackish-water fishes will become more readily available when the market demand is there. In the mean time, we can focus on some of the cool fishes from these habitats which are currently available to us, like our pal the Orange Chromide. And the brackish water habitats are as interesting, dynamic, and bountiful as any on the planet.
There is still a surprisingly large amount of misinformation about there concerning fishes long thought to be "brackish", when the reality is that they are often found predominantly in non-brackish habitats, with perhaps only isolated populations of fishes being brackish fishes.
Fortunately for us, our friend the Orange Chromide is one of those which you can do the research on and find a surprisingly large amount of interesting, scholarly information out there.
You just have to be willing to look.
Stay motivated. Stay curious. Stay excited. Stay diligent. Stay persistent...
And Stay Wet.