The Botanical-Style Aquarium: A "filter" of its own, and other biological musings...

A big thought about our botanical-style aquariums:

The aquarium-or, more specifically- the botanical materials which comprise the botanical-style aquarium "infrastructure" acts as a biological "filter system."

In other words, the botanical materials present in our systems provide enormous surface area upon which beneficial bacterial biofilms and fungal growths can colonize. These life forms utilize the organic compounds present in the water as a nutritional source.

Oh, the part about the biofilms and fungal growths sounds familiar, doesn't it?

Let's talk about our buddies, the biofilms, just a bit more. One more time. Because nothing seems as contrary to many hobbyists than to sing the praises of these gooey-looking strands of bacterial goodness!

Structurally, biofilms are surprisingly strong structures, which offer their colonial members "on-board" nutritional sources, exchange of metabolites, protection, and cellular communication. They form extremely rapidly on just about any hard surface that is submerged in water.

When I see aquarium work in which biofilms are considered a "nuisance", and suggestions that it can be eliminated by "reducing nutrients" in the aquarium, I usually cringe. Mainly, because no matter what you do, biofilms are ubiquitous, and always present in our aquariums. We may not see the famous long, stringy "snot" of our nightmares, but the reality is that they're present in our tanks regardless.

The other reality is that biofilms are something that we as aquarists typically fear because of the way they look. In and of themselves, biofilms are not harmful to our fishes. They function not only as a means to sequester and process nutrients ( a "filter" of sorts?), they also represent a beneficial food source for fishes.

Now, look, I can see rare scenarios where massive amounts of biofilms (relative to the water volume of the aquarium) can consume significant quantities of oxygen and be problematic for the fishes which reside in your tank. These explosions in biofilm growth are usually the result of adding too much botanical material too quickly to the aquarium. They're excaserbated by insufficient oxygenation/circulation within the aquarium.

These are very unusual circumstances, resulting from a combination of missteps by the aquarist.

Typically, however, biofilms are far more beneficial that they are reven emotely detrimental to our aquariums.

Nutrients in the water column, even when in low concentrations, are delivered to the biofilm through the complex system of water channels, where they are adsorbed into the biofilm matrix, where they become available to the individual cells.  Some biologists feel that this efficient method of gathering energy might be a major evolutionary advantage for biofilms which live in particularly in turbulent ecosystems, like streams, (or aquariums, right?) with significant flow, where nutrient concentrations are typically lower and quite widely dispersed.

Biofilms have been used successfully in water/wastewater treatment for well over 100 years! In such filtration systems the filter medium (typically, sand) offers a tremendous amount of surface area for the microbes to attach to, and to feed upon the organic material in the water being treated. The formation of biofilms upon the "media" consume the undesirable organics in the water, effectively "filtering" it!

Biofilm acts as an adsorbent layer, in which organic materials and other nutrients are concentrated from the water column. As you might suspect, higher nutrient concentrations tend to produce biofilms that are thicker and denser than those grown in low nutrient concentrations.

Those biofilms which grow in higher flow environments, like streams, rivers, or areas exposed to wave action, tend to be denser in their morphology. These biofilms tend to form long, stringy filaments or "streamers",which point in the direction of the flow. These biofilms are characterized by characteristic known as  "viscoelasticity." This means that they are flexible, and stretch out significantly in higher flow rate environments, and contract once again when the velocity of the flow is reduced.

Okay, that's probably way more than you want to know about the physiology of biofilms! Regardless, it's important for us as botanical-style aquarists to have at least a rudimentary understanding of these often misunderstood, incredibly useful, and entirely under-appreciated life forms.

And the whole idea of facilitating a microbiome in our aquariums is predicated upon supplying a quantity of botanical materials- specifically, leaf litter, for the beneficial organisms to colonize and begin the decomposition process. An interesting study I found by Mehering, et. al (2014) on the nutrient sequestration caused by leaf litter yielded this interesting little passage:

"During leaf litter decomposition, microbial biomass and accumulated inorganic materials immobilize and retain nutrients, and therefore, both biotic and abiotic drivers may influence detrital nutrient content."

The study determined that leaves such as oak "immobilized" nitrogen. Generally thinking, it is thought that leaf litter acts as a "sink" for nutrients over time in aquatic ecosystems.

Oh, and one more thing about leaves and their resulting detritus in tropical streams: Ecologists strongly believe that microbial colonized detritus is a more palatable and nutritious food source for detritivores than uncolonized dead leaves. The microbial growth which occurs on the leaves and their resulting detritus increases the nutritional quality of leaf detritus, because the microbial biomass on the leaves is more digestible than the leaves themselves (because of lignin, etc.).

Okay, great. I've just talked about decomposing leaves and stuff for like the 11,000th time in "The Tint"; so...where does this leave us, in terms of how we want to run our aquariums?

Let's summarize:

1) Add a significant amount of leaf litter, twigs, and botanicals to your aquarium as part of the substrate.

2) Allow biofilms and fungal growths to proliferate.

3) Feed your fishes well. It's actually "feeding the aquarium!"

4) Don't go crazy siphoning out every bit of detritus.

Let's look at each of these points in a bit more detail.

First, make liberal use of leaf litter in your aquarium. I'd build up a layer anywhere from 1"-4" of leaves. Yeah, I know- that's a lot of leaves. Initially, you'll have a big old layer of leaves, recruiting biofilms and fungal growths on their surfaces. Ultimately, it will decompose, creating a sort of "mulch" on the bottom of your aquarium, rich in detritus, providing an excellent place for your fishes to forage among. 

Allow a fair amount of indirect circulation over the top of your leaf litter bed. This will ensure oxygenation, and allow the organisms within the litter bed to receive an influx of water (and thus, the dissolved organics they utilize). Sure, some of the leaves might blow around from time to time- just like what happens in Nature. It's no big deal- really!

The idea of allowing biofilms and fungal growths to colonize your leaves and botanicals, and to proliferate upon them simply needs to be accepted as fundamental to botanical-style aquarium keeping. These organisms, which comprise the biome of our aquariums, are the most important "components" of the ecosystems which our aquariums are.

I'd be remiss if I didn't at least touch on the idea of feeding your aquarium. Think about it: When you feed your fishes, you are effectively feeding all of the other life forms which comprise this microbiome. You're "feeding the aquarium." When fishes consume and eliminate the food, they're releasing not only dissolved organic wastes, but fecal materials, which are likely not fully digested. The nutritional value of partially digested food cannot be understated. Many of the organisms which live within the botanical bed and the resulting detritus will assimilate them.

Now, we could go on and on about this topic; there is SO much to discuss. However, let's just agree that feeding our fishes is another critical activity which provides not only for our fishes' well-being, but for the other life forms which create the ecology of the aquarium.

And, let's be clear about another thing: Detritus, the nemesis of many aquarists- is NOT our enemy. We've talked about this for several years now, and I cannot stress it enough: To remove every bit of detritus in our tanks is to deprive someone, somewhere along the food chain in our tanks, their nutritional source. And when you do that, imbalances occur...You know, the kinds which cause "nuisance algae" and those "anomalous tank crashes."

The definition of this stuff, as accepted in the aquarium hobby, is kind of sketchy in this regard; not flattering at the very least:

"detritus is dead particulate organic matter. It typically includes the bodies or fragments of dead organisms, as well as fecal material. Detritus is typically colonized by communities of microorganisms which act to decompose or remineralize the material."

Shit, that's just bad branding.

The reality is that this not a "bad" thing. Detritus, like biofilms and fungi, is flat-out misunderstood in the hobby.

Could there be some "upside" to this stuff? 

Of course there is. 

I mean, even in the above the definition, there is the part about being "colonized by communities of microorganisms which act to decompose or remineralize..."

It's being processed. Utilized. What do these microorganisms do? They eat it...They render it inert. And in the process, they contribute to the biological diversity and arguably even the stability of the system. Some of them are utilized as food by other creatures. Important in a closed system, I should think.

This is really important. It's part of the biological operating system of our botanical-style aquariums. I cannot stress this enough. 

Now, I realize that the idea of embracing this stuff- and allowing it to accumulate, or even be present in your system- goes against virtually everything we've been indoctrinated to believe in about aquarium husbandry. Pretty much every article you see on this stuff is about its "dangers", and how to get it out of your tank. I'll say it again- I think we've been looking at detritus the wrong way for a very long time in the aquarium hobby, perceiving it as an "enemy" to be feared, as opposed to the "biological catalyst" it really is!

In essence, it's organically rich particulate material that provides sustenance, and indeed, life to many organisms which, in turn, directly benefit our aquariums.

We've pushed this narrative many times here, and I still think we need to encourage hobbyists to embrace it more.

Yeah, detritus.

Okay, I'll admit that detritus, as we see it, may not be the most attractive thing to look at in our tanks. I'll give you that. It literally looks like a pile of shit! However, what we're talking about allowing to accumulate isn't just fish poop and uneaten food. It's broken-down materials- the end product of biological processing.  And, yeah, a wide variety of organisms have become adapted to eat or utilize detritus.

There is, of course, a distinction.

One is the result of poor husbandry, and of course, is not something we'd want to accumulate in our aquariums. The other is a more nuanced definition. 

As we talk about so much around here- just because something looks a certain way doesn't mean that it alwaysa bad thing, right?

What does it mean? Take into consideration why we add botanicals to our tanks in the first place. Now, you don't have to have huge piles of the stuff littering your sandy substrate. However, you could have some accumulating here and there among the botanicals and leaves, where it may not offend your aesthetic senses, and still contribute to the overall aquatic ecosystem you've created.

If you're one of those hobbyists who allows your leaves and other botanicals to break down completely into the tank, what really happens? Do you see a decline in water quality in a well-maintained system? A noticeable uptick in nitrate or other signs? Does anyone ever do water tests to confirm the "detritus is dangerous" theory, or do we simply rely on what "they" say in the books and hobby forums?

Is there ever a situation, a place, or a circumstance where leaving the detritus "in play" is actually a benefit, as opposed to a problem?

I think so. Like, almost always.

Yes, I know, we're talking about a closed ecosystem here, which doesn't have all of the millions of minute inputs and exports and nuances that Nature does, but structurally and functionally, we have some of them at the highest levels (ie; water going in and coming out, food sources being added, stuff being exported, etc.).

There is so much more to this stuff than to simply buy in unflinchingly to overly-generalized statements like, "detritus is bad."

The following statement may hurt a few sensitive people. Consider it some "tough love" today: 

If you're not a complete incompetent at basic aquarium husbandry, you won't have any issues with detritus being present in your aquarium.

Just:

Don't overstock.

Don't overfeed.

Don't neglect regular water exchanges.

Don't fail to maintain your equipment.

Don't ignore what's happening in your tank.

This is truly not "rocket science." It's "Aquarium Keeping 101."

And it all comes full circle when we talk about "filtration" in our aquariums.

People often ask me, "What filter do you use use in a botanical-style aquarium?" My answer is usually that it just doesn't matter.  You can use any type of filter. The reality is that, if allowed to evolve and grow unfettered, the aquarium itself- all of it- becomes the "filter." 

You can embrace this philosophy regardless of the type of filter that you employ.

My sumps and integrated filter compartments in my A.I.O. tanks are essentially empty.

I may occasionally employ some activated carbon in small amounts, or throw some "Shade" sachets in there if I am feeling it- but that's it. The way I see it- these areas, in a botanical-style aquarium, simply provide more water volume, more gas exchange; a place for bacterial attachment (surface area), and perhaps an area for botanical debris to settle out. Maybe I'll remove them, if only to prevent them from slowing down the flow rate of my return pumps.

But that's it. 

A lot of people are initially surprised by this. However, when you look at it in the broader context of botanical style aquariums as miniature ecosystems, it all really makes sense, doesn't it? The work of these microorganisms and other life forms takes place throughout the aquarium.

I admit, there was a time when I was really fanatical about making sure every single bit of detritus and fish poop and all that stuff was out of my tanks. About undetectable nitrate. I was especially like that in my earlier days of reef keeping, when it was thought that cleanliness was the shit!

It wasn't until years into my reef keeping work, and especially in my coral propagation work, that I begin to understand the value of food, and the role the it plays in aquatic ecosystems as a whole. And that "food" means different things to different aquatic organisms. The idea of scrubbing and removing every single trace of what we saw as "bad stuff" from our grow-out raceways essentially deprived the corals and supporting organisms of an important natural food source.

We'd fanatically skim and remove everything, only to find out that...our corals didn't look all that good. We'd compensate by feeding more heavily, only to continue to remove any traces of dissolved organics from the water...

It was a constant struggle- the metaphorical "hamster wheel"- between keeping things "clinically clean" and feeding our animals. We were super proud of our spotless water. We had a big screen when you came into our facility showing the parameters in each raceway. Which begged the question: Were we interested in creating sterile water, or growing corals? 

Eventually, it got through my thick skull that aquariums- just like the wild habitats they represent-are not spotless environments, and that they depend on multiple inputs of food, to feed the biome at all levels. This meant that scrubbing the living shit (literally) out of our aquariums was denying the very biotia which comprised our aquariums their most basic needs.

That little "unlock" changed everything for me.

Suddenly, it all made sense. 

This has carried over into the botanical-style aquarium concept: It's a system that literally relies on the biological material present in the system to facilitate food production, nutrient assimilation, and reproduction of life forms at various trophic levels.

It's changed everything about how I look at aquarium management and the creation of functional closed aquatic ecosystems. 

It's really put the word "natural" back into the aquarium keeping parlance for me. The idea of creating a multi-tiered ecosystem, which provides a lot of the requirements needed to operate successfully with just a few basic maintenance practices, the passage of time, a lot of patience, and careful observation.

It means adopting a different outlook, accepting a different, yet very beautiful aesthetic. It's about listening to Nature instead of the asshole on Instagram with the flashy, gadget-driven tank. It's not always fun at first for some, and it initially seems like you're somehow doing things wrong.

It's about faith. Faith in Mother Nature, who's been doing this stuff for eons.

It's about nuance.

It's about looking at things a bit different that we've been "programmed" to do in the aquarium hobby for so long. It's about not being afraid to question the reasons why we do things a certain way in the hobby, and to seek ways to evolve and change practices for the benefits of our fishes. 

It takes time to grasp this stuff. However, as with so many things that we talk about here, it's not revolutionary...it's simply an evolution in thinking about how we conceive, set up, and manage our aquariums. 

 

Sure, the aquairum is a "filter" of sorts, if you want to label it as such. However, it's so much more: A small, evolving ecosystem, relying on natural processes to bring it to life.

Wrap you head around that.

It might just change everything in the hobby for you.

Stay open-minded. Stay thoughtful. Stay bold. Stay curious. Stay diligent. Stay observant...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

 

 

 

 

Botanical materials in the wild...and in the aquarium: Influences and Impacts.

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. 

Yeah, dynamic.

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!

Whoa!

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.

 

Scott Fellman

Tannin Aquatics 

 

Evolving techniques

It's kind of fun to make little "tweaks" or adjustments to our aquarium methodology or approaches to how we do certain things. This is what pushes the state of the art in aquaristics further down the road. Now, not every one of these adjustments is a quantum leap forward, at least, not initially. Many are simply subtle iterations of things we've played with before.

An example?

One of our fave approaches, sort of derived out of our "Urban Igapo" work, has been to "dry set" the aquarium.  A sort of technique I call the "transitional approach." 

Basically, all you're doing is adding the prepared botanicals and leaves to your aquarium before it's filled, and spraying them down with water and our sprayable Purple Non-Sulphur bacterial inoculant, "Nurture" to kick-start the biological processes. Let it sit. Spray it down daily.

Then fill it.

Unlike in our "Urban Igapo" approach, you're not trying to grow terrestrial grasses or plants during the "dry phase." You're simply creating and managing  what will ultimately be the submerged habitat in your aquarium for a while before filling it.

I've done this a number of times and had great results.

Stupidly simple. Yet, profoundly different.

Why?

Because, rather than our "traditional" approach of adding the botanicals and leaves to the aquarium after it's already filled, you're sort of replicating what happens in Nature in the wild when forest floors and other terrestrial environments are inundated by overflowing streams and rivers.

The thing I like about this approach (besides how it replicates what happens in the wild) is that it gives you the ability to really saturate and soften  the botanicals and leaves, and to begin the process of decomposition and bacterial colonization before you add the water. 

When do you fill the aquarium?

You can wait a few days, a week or two, or as long s you'd like, really. The idea is to get the materials physically placed, and to begin the process of colonization and "softening" by fungi and bacterial biofilms- known as "conditioning" by ecologists who study these habitats. 

And of course, fishes and invertebrates which live amongst and feed directly upon the fungi and decomposing leaves and botanicals will contribute to the breakdown of these materials as well! Aquatic fungi can break down the leaf matrix and make the energy available to feeding animals in these habitats. And look at this little gem I found in my research:

"There is evidence that detritivores selectively feed on conditioned leaves, i.e. those previously colonized by fungi (Suberkropp, 1992; Graca, 1993). Fungi can alter the food quality and palatability of leaf detritus, aecting shredder growth rates. Animals that feed on a diet rich in fungi have higher growth rates and fecundity than those fed on poorly colonized leaves. Some shredders prefer to feed on leaves that are colonized by fungi, whereas others consume fungal mycelium selectively..."

"Conditioned" leaves, in this context, are those which have been previously colonized by fungi! They make the energy within the leaves and botanicals more available to higher organisms like fishes and invertebrates! 

We've long maintained that the appearance of biofilms and fungi on your botanicals and wood are to be celebrated- not feared. They represent a burgeoning emergence of life -albeit in one of its lowest and most unpleasant-looking forms- and that's a really big deal. 

"Oh shit, he's going to talk about biofilms AGAIN!"

Well, just for a second.

Biofilms, as we probably all know by now, form when bacteria adhere to surfaces in some form of watery environment and begin to excrete a slimy, gluelike substance, consisting of sugars and other substances, that can stick to all kinds of materials, such as- well- in our case, botanicals. It starts with a few bacteria, taking advantage of the abundant and comfy surface area that leaves, seed pods, and even driftwood offer.

The "early adapters" put out the "welcome mat" for other bacteria by providing more diverse adhesion sites, such as a matrix of sugars that holds the biofilm together. Since some bacteria species are incapable of attaching to a surface on their own, they often anchor themselves to the matrix or directly to their friends who arrived at the party first.

It's a literal explosion of life. It's a gift from Nature. And we can all receive it and benefit from it! 

Another advantage of this approach? The traditional "cycling" time of a new tank seems to go much faster. Almost undetectable, in many of my experiments. I can only hypothesize and assume that it's likely a result of all of the bacterial growth in the "terrestrial" phase, and the concurrent  "conditioning" of the botanical materials.  

Tannin's creative Director, Johnny Ciotti, calls this period of time when the biofilms emerge, and your tank starts coming alive "The Bloom"- a most appropriate term, and one that conjures up a beautiful image of Nature unfolding in our aquariums- your miniature aquatic ecosystem blossoming before your very eyes!

The real positive takeaway here: Biofilms are really a sign that things are working right in your aquarium! A visual indicator that natural processes are at work, helping forge your tank's ecosystem.

So, what about the botanicals?

The idea of utilizing botanicals in the aquarium can be whatever you want, sure. However, if you ask me (and you likely didn't)- the idea of utilizing these materials in our tanks has always been to create unique environmental conditions and foster a biome of organisms which work together to form a closed microcosm. That is incredible to me.

And the idea of "dry setting" your botanical materials and sort of "conditioning" them before adding the water, this "transitional approach", while not exactly some "revolutionary" thing, IS an evolutionary step in the development of botanical-style aquarium keeping.

The "transitional approach" is definitely a bit different than what we've done in the past, and may create a more stable, more biologically diverse aquarium, because you're already fostering a biome of organisms which will make the transition to the  aquatic habitat and "do their thing" that much more quickly.

This IS unique.

We're talking about actually allowing some of the decomposition to start before water is ever added to our tanks. It's a functional approach, requiring understanding, research, and patience to execute. There's really nothing difficult about it.

And the aesthetics? They're going to be different than what you're used to, no doubt. They will follow as a result of the process, and will resemble, on a surprisingly realistic level, what you see in Nature.

But the primary reason is NOT for aesthetics... 

 

The interactions and interdependencies between terrestrial and aquatic habitats are manifold, beneficial, and quite compelling to us as hobbyists. To be able to study this dynamic first hand, and to approach it somewhat methodically, is a significant change in our technique.

And yeah, it's almost absurdly easy to do.

The hard part is that it requires a bit more patience; not everyone will see the advantages, or value, and the trade-off between waiting to fill your tank and filling it immediately. It may not be one that some are willing to make.

If you do, however, you will get to see, firsthand, the fascinating dynamic between the aquatic and the terrestrial environment in a most intimate way.

It could change your thinking about how we set up aquariums. 

It could.

At the most superficial level, it's an acknowledgement that, after many decades, we as hobbyists are acknowledging and embracing this terrestrial-aquatic dynamic. It's a really unique approach, because it definitely goes against the typical "aquatic only" approach that we are used to.

 

 

When you consider that many aquatic habitats start out as terrestrial ones, and accumulate botanical materials and provide colonization points for various life forms, and facilitate biological processes like nutrient export and production of natural food resources, the benefits are pretty obvious. Again, the "different aesthetics" simply come along as "part of the package"- both in Nature and in the aquarium.

Replicating this process and managing it in the aquarium also provides us as hobbyists highly unique insights into the function of these habitats. 

From a hobby perspective, evolving and managing a closed ecosystem is really something that we should take to easily.

Setting up an aquarium in this fashion also provides us with the opportunity to literally "operate" our botanical-style aquariums; that is, to manage their evolution over time through deliberate steps and practices is not entirely unknown to us as aquarium hobbyists.

It's not at all unlike what we do with planted aquarium or reef aquarium. In fact, the closest analog to this approach is the so-called "dry start" approach to planted aquariums, except we're trying to grow bacteria and other organisms instead of plants.

Yes, it's an evolution.

Simply, a step forward out of the artificially-induced restraints of "this is how it's always been done"- even in our own "methodology"- yet another exploration into what the natural environment is REALLY like, how it evolves, and how it works- and understanding, embracing and appreciating its aesthetics, functionality, and richness.  

Earth-shattering? Not likely.

Educational? For sure.

Thought provoking and fun? Absolutely.

A simple, yet I think profound "tweak" to our approach.

Stay curious. Stay open-minded. Stay thoughtful. Stay observant. Stay creative.

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

 

Cool Places.

As you know, we receive a lot of questions around here about all sorts of aquarium-related topics. Usually, my answer is directly to the individual who asked, in the form of an email or DM. Sometimes, however, the answer is such that it is best addressed in the form of a blog post! 

Recently, a hobbyist asked me what my opinion was of the botanical-style aquarium as a type of "aquascaping approach", and how it fits in the overall aquascaping "universe." Exactly what our "thing" is...

First, I start with my assertion that the botanical-style aquarium is NOT an aquascaping "style"- it's a methodology to create a more natural-functioning aquarium by utilizing botanical materials to "fuel" the process. The look is a "collateral benefit" of the methodology.

I admit, I've never really been much of an "aquascaper."

You know- those hobbyists who can take a few rocks and a piece or two of wood and turn them into some sort of amazing design. That takes amazing talent and vision. And I made peace with that decades ago! I greatly admire those true artists who can employ all sorts of technique, color-coordination, and ratio and such snd come up with some incredible stuff with seeming ease.

On the other hand, I look at a lot of aquascaping work, admire the effort and talent  and such, and then get this feeling in my gut that I can't always explain. Well, I can, but it's not always...nice. Like, I look at many "modern scapes" and just kind of...yawn.

Ouch, I'm sounding like a proper asshole, I know.

But seriously, it's not that I think their work is shitty or something...I just find the "styles" of many of the beautiful tanks out there which the world goes crazy over to be just a bit..boring. Or, should I say- not my taste. Yeah, that's better.

It's weird, I do like certain planted tanks that just blow me away. Our friend, George Farmer, does amazing planted 'scapes which I would happily have in my own home if I had the talent. I love the work of our own Johnny Ciotti- a guy who was trained as a classic "Nature Aquarium Style" 'scaper, yet, a true artist who can take botanical elements and create stunning botanical-style aquariums with ease. Jeff Sense of Aquarium Design Group is another person who can work with just about any "media" you give him- rocks, wood, plants- and crank out something that is unmistakingly original, dynamic, and gorgeous.

 

I'll never be as talented as those guys. And I'm perfectly okay with that. I'm comfortable in my own skin. And it's largely because, a long time ago, I found what I truly love, and work with that. I think we should all have that degree of comfort with what we love. Sadly, many hobbyists don't- and feel that-in order to be considered "talented" or whatever- that they have to embrace a certain style or technique.

That's absurd.

I often think about the so-called "diorama style" tanks that pop up in contests, and are all over Instagram or whatever. They require enormous talent to execute, but they're far more "art" than they are "natural aquariums", I suppose. And I guess that's what gets me- these weird fantasy scapes have live plants and glued-together rock and wood and stuff, but they are anything but "natural", IMHO.

I guess what gets me is that the aquascaping world lauds these scapes as "the shit"- and sure, they are fantastic- amazing work. When they're called "natural", that sends shivers down my spine...I mean, doesn't Nature offer scenes that are equally as complex, interesting, and challenging to pull off? And, with the added bonus that you can replicate the function of these habitats, I can't see why you don't see more representations of flooded forests, vernal pools, Pantanal meadows, etc. in the major aquascaping contests.

I imagine how amazing a tank one of those diorama-style 'scapers could pull off if he/she tried to replicate an actual aquatic habitat as found in Nature. With there talent and ability to bring a vision to life....wow! I mean, sure, such a tank won't have a beach scene, winding road into a forest, or a mountain range, or any of that other cliche stuff- but it will have all of the amazing vibrancy and intricate structure of natural aquatic habitats. The possibilities are endless.

 

I've postulated about why we don't see more of these things in contests..

However,  the benefits of entering tanks like this would be many, including calling attention to the wonders of the natural world, and the precious wild habitats which are often threatened by human activities.

I think that a good part of the reason is that these natural habitats aren't "tight" from a design standpoint. They don't -on the surface, at least-seem to require any "discipline" in order to replicate. You have to cede a certain amount of your work to Nature. I think that freaks out a lot of artistic aquascapers.

Nature, and Her many ecological niches and features, provides an endless array of habitats to recreate in the home aquarium. And my "POV" has always been to look at these niches, figure out how and why they formed, and why they look the way that they do. By researching the processes which helped create the habitat, I'm challenged to create an aquarium which attempts to replicate both the form and the function of it.

Some of these habitats are not what you'd expect to see in an aquairum. They look- and function- fundamentally different from what we've worked with before.

Some of the aesthetics of these wild habitats freaks people out. They look so...random...so...undisciplined, if we were to ascribe artistic terms to them. It's a world where we set up the system to allow Nature to do the "finishing" work. It require s a certain trust in natural processes, and the ability to let go. The ability to realize that what we see is a "finished product" is only the very beginning.

"The Delta at the intersection between science and art.” 

That's where I play. 

I like it here. A lot of you do, too.

This "not quite a biotope aquarium" and "not quite an artistic aquascape" thing is the perfect "sweet spot" for my interest, attention, and skills. And I think it's the place where I can be most useful to the hobby. Biotope-inspired, I suppose. A more forgiving, easygoing "style" which places function over aesthetics, yet somehow always leads to something that I find aesthetically pleasing.

 

It's a strange, yet wonderful place, where I've made the many "mental shifts" that allow me to enjoy the beauty and elegance of stuff like decomposing leaves, sediment, biofilms, fungal growths, random aggregations of leaves, etc. A place where much of the attraction is because the aquariums I create are intended to let Nature do some of the work. 

If I were forced (and yeah, "forced" is the right word, because there are no defining "rules" here...no way) to offer some defining characteristics of the  "botanical-style" aquarium, I'd say that a certain "randomness", actually, is it.

I mean, we're all about replicating what happens in Nature, NOT about perfectly proportioned placements and such. Now, I must admit, some of the world-class aquascapers that have worked with our botanicals have applied these concepts to these types of aquariums and have produced stunning results.

However, I think the "raw" botanical aquarium "essence" is about a certain degree of randomness.

And then there are details which nature can do best.

 

Details.

I believe that an aquarium that attempts to replicate a scene like the ones we're talking about starts with what looks like really artificial placement of wood, anchored by numerous details which soften, define, and fill in the scape. A sort of analog to the theater/motion picture concept  of "mise en scene", where pieces literally set the stage and help tell a story by providing context.

Yes, unlike a scape which depends upon growth of plants to fill it in and "evolve" it, the botanical-style blackwater/brackish aquarium is largely hardscape materials, which requires the adept placement of said materials to help fill in the scene. And of course, part of the "evolution" is the softening, redistribution, and break down of botanical materials over time...just like what happens in nature.

I suppose this little rant could be viewed as a "defense" our "style", which on occasion has been criticized as "sloppy", "lazy", "undisciplined", etc...😆

Perhaps it is to some. However, I think it serves to re-examine what I feel is one of the foundational philosophies of the botanical-style aquarium "aesthetic."

I must confess, it's an aesthetic which certainly doesn't appeal to everyone. In fact, many in the mainstream aquascaping world tended to levy all sorts of "constructive criticisms" and "Yeah, but..." comments about our practices and ideas for a while...Less these days, BTW!

And that is part of the attraction of this the of aquarium for me. Rather than conform thoroughly to some sort of "rules" based on design, layout, and technique, this type of aquarium tends to ask for very basic initial design, and lets Mother Nature handle a lot of the emerging details over time.

I think that there is a certain hunger for something different in the hobby right now.  I feel that we've dedicated most of this century to figuring out ways to push back against Nature's processes. We've spent a tremendous amount of time looking for ways to remove things that we don't feel belong in our tanks: Algae, biofilms, decomposition, etc. Stuff that we, as a hobby, feel to be unwelcome, unattractive, and even "detrimental."

And quite honestly, I think we see these things as undesirable or "unsafe" because they are artifacts of outdated thinking...holdovers from a time when we felt that our technology gave us the edge to accomplish what Nature couldn't. 

And of course, the reality is that the technology can accomplish some of these things, like nutrient export, heat control, circulation, etc.-but what really powers the miniature ecosystems which our aquariums actually are- is the microbiome: Fungal growths, bacterial biofilms, the process of decomposition, etc. Stuff which looks distasteful to many, yet stuff that is fundamental to the function-and yeah, the look- of our tanks. 

It's not just a look. Not just an aesthetic. Not just a mindset...

It's a way to incorporate natural materials to achieve new and progressive results with the fishes and plants we've come to love so much.

And, It's still early days.

A ground floor opportunity for every aquarist who gives this stuff a shot to make a meaningful- and beautiful contribution to the evolving state of the art of the botanical-style aquarium., and to share what Nature really looks like with people all over the world.

I'm fascinated by the "mental adjustments" that we need to make to accept the aesthetic and the processes of natural decay, fungal growth, the appearance of biofilms, and how these affect what's occurring in the aquarium. It's all a complex synergy of life and aesthetic.

And we have to accept Nature's input here.

Nature dictates the speed by which this decomposition process occurs. We set the stage for it- but  Nature is in full control. As an aquarist with a botanical-style aquarium, it's our "job" to observe and know when- or if- to intervene by adding or removing botanicals as they break down.

The great Takashi Amano's whole idea in a nutshell was to replicate Nature to a certain extent by accepting it and laying a conceptual groundwork for it to unfold. (Just look at all of the pics of grassy fields and moss-covered fenceposts in Amano's books. He got it. He felt something.) Now, granted, his general aesthetic involved plants and what seems to be a natural-looking aquascape, although executed in an intentionally artistic way.

There is nothing wrong with this. Some of the world's most beautiful aquariums were/are created this way. 

However, what I noticed over time in the freshwater world was an almost obsessive, rigid adherence to certain parts of Amano's formula and aesthetic; specifically, ratios, placement of hardscape and plants, and a certain type of aesthetic formula that one had to replicate in order to gain legitimacy or "acceptance" from the community. 

I really don't think it was Amano's intent.

"Wabi-sabi", the Japanese philosophy which embraces the ephemeral nature of the existence of things, was/is a key concept in Amano's approach, and it still is.

I think it's fallen into a bit of "disuse", though, in the "Nature Aquarium" movement, as aquarists aspired to replicate the style proffered in his works, perhaps trying to by-pass what seemed to be a less exciting -or less immediately rewarding- part of his approach.

I think that this is why we have some many  "diorama-style" tanks in competitions, with "details" like twigs and roots glued to wood...and I also think it's why we see more and more serious aquascapers taking another look at a more realistic type of aquarium utilizing botanicals. Aquariums which embrace decay, detritus, biofilms, and a less "ratio-centric", more "random" natural look.

I think many aquascapers are simply tired of overly-stylized and are leaning back into a truly more natural look. And maybe...perhaps- they're starting to come around to the idea of "functional aesthetics', too!

 A less rigidly aesthetically-controlled, less "high-concept" approach to setting the stage for...Nature- to do what she's done for eons without doing as much to "help it along." Rather, the mindset here is to allow nature to take it's course, and to embrace the breakdown of materials, the biofilms, the decay...and rejoice in the ever-changing aesthetic and functional aspects of a natural aquatic system- "warts and all" -and how they can positively affect our fishes.

Wabi-Sabi? Yeah, I think so. I think we embody the concept beautifully.

The initial skepticism and resistance to the idea of an aquarium filled with biofilms, decomposition, and tinted water has given way to enormous creativity and discovery. Our community has (rather easily, I might add!) accepted the idea that Nature will follow a certain "path"- parts of which are aesthetically different than anything we've allowed to occur in our tanks before- and rather than attempting to mitigate, edit, or thwart it, we're celebrating it!

"Functional aesthetics."

I think this is where Tannin Aquatics falls, if you had to nail us down into one specific "stylistic/philosphical approach" to aquariums.

The "space between", so to speak. Sort of straddling multiple approaches, with Nature as the ultimate "critic."

This can take us to some really cool places.

Let's go there.

Stay creative. Stay excited. Stay bold. Stay thoughtful...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

What our fishes eat...The wonder of food webs.

Yes, I admit that we talk about some rather obscure topics around here. Yet, many of these topics are actually pretty well known, and even well-understood by science. We just haven't consciously applied them to our aquarium work...yet.

One of the topics that we talk about a lot are food webs. To me, these are fascinating, fundamental constructs which can truly have important influence on our aquariums.

So, what exactly is a food web?

 

A food web is defined by aquatic ecologists as a series of "trophic connections" (ie; feeding and nutritional resources in a given habitat) among various species in an aquatic community. 

All food chains and webs have at least two or three of these trophic levels. Generally, there are a maximum of four trophic levels. Many consumers feed at more than one trophic level.

So, a trophic level in our case would go something like this: Leaf litter, bacteria/fungal growth, crustaceans...

In the wild aquatic habitats we love so much, food webs are vital to the organisms which live in them. They are an absolute model for ecological interdependencies and processes which encompass the relationship between the terrestrial and aquatic environments.

In many of the blackwater aquatic habitats that we're so obsessed with around here, like the Rio Negro, for example, studies by ecologists have determined that the main sources of autotrophic sources are the igapo, along with aquatic vegetation and various types of algae. (For reference, autotrophs are defined as organisms that produce complex organic compounds using carbon from simple substances, such as CO2, and using energy from light (photosynthesis) or inorganic chemical reactions.)

Hmm. examples would be phytoplankton!

Now, I was under the impression that phytoplankton was rather scarce in blackwater habitats. However, this indicates to scientists is that phytoplankton in blackwater trophic food webs might be more important than originally thought! 

Now, lets get back to algae and macrophytes for a minute. Most of these life forms enter into food webs in the region in the form of...wait for it...detritus! Yup, both fine and course particular organic matter are a main source of these materials. I suppose this explains why heavy accumulations of detritus and algal growth in aquaria go hand in hand, right? Detritus is "fuel" for life forms of many kinds.

In Amazonian blackwater rivers, studies have determined that the aquatic insect abundance is rather low, with most species concentrated in leaf litter and wood debris, which are important habitats.  Yet, here's how a food web looks in some blackwater habitats : Studies of blackwater fish assemblages indicated that many fishes feed primarily on burrowing midge larvae (chironomids, aka "Bloodworms" ) which feed mainly with organic matter derived from terrestrial plants!

And of course, allochtonous inputs (food items from outside of the ecosystem), like fruits, seeds, insects, and plant parts, are important food sources to many fishes.  Many midwater characins consume fruits and seeds of terrestrial plants, as well as terrestrial insects.

Insects in general are really important to fishes in blackwater ecosystems. In fact, it's been concluded that the the first link in the food web during the flooding of forests is terrestrial arthropods, which provide a highly important primary food for many fishes.

These systems are so intimately tied to the surrounding terrestrial environment. Even the permanent rivers have a strong, very predictable "seasonality", which  provides fruits, seeds, and other terrestrial-originated food resources for the fishes which reside in them. It's long been known by ecologists that rivers with predictable annual floods have a higher richness of fish species tied to this elevated rate of food produced by the surrounding forests.

 

 

And of course, fungal growths and bacterial biofilms are also extremely valuable as food sources for life forms at many levels, including fishes. The growth of these organisms is powered by...decomposing leaf litter! 

Sounds familiar, huh?

So, how does a leaf break down? It's a multi-stage process which helps liberate its constituent compounds for use in the overall ecosystem. And one that is vital to the construction of a food web.

The first step in the process is known as leaching, in which nutrients and organic compounds, such as sugars, potassium, and amino acids dissolve into the water and move into the soil.The next phase is a form of fragmentation, in which various organisms, from termites (in the terrestrial forests) to aquatic insects and shrimps (in the flooded forests) physically break down the leaves into smaller pieces. 

As the leaves become more fragmented, they provide more and more surfaces for bacteria and fungi to attach and grow upon, and more feeding opportunities for fishes!

Okay, okay, this is all very cool and hopefully, a bit interesting- but what are the implications for our aquariums? How can we apply lessons from wild aquatic habitats vis a vis food production to our tanks? 

This is one of the most interesting aspects of a botanical-style aquarium: We have the opportunity to create an aquatic microcosm which provides not only unique aesthetics- it provides nutrient processing, and to some degree, a self-generating population of creatures with nutritional value for our fishes, on a more-or-less continuous basis.

Incorporating botanical materials in our aquariums for the purpose of creating the foundation for biological activity is the starting point. Leaves, seed pods, twigs and the like are not only "attachment points" for bacterial biofilms and fungal growths to colonize, they are physical location for the sequestration of the resulting detritus, which serves as a food source for many organisms, including our fishes.

Think about it this way: Every botanical, every leaf, every piece of wood, every substrate material that we utilize in our aquariums is a potential component of food production!

The initial setup of your botanical-style aquarium will rather easily accomplish the task of facilitating the growth of said biofilms and fungal growths. There isn't all that much we have to do as aquarists to facilitate this but to simply add these materials to our tanks, and allow the appearance of these organisms to happen. 

 

You could add pure cultures of organisms such as Paramecium, Daphnia, species of copepods (like Cyclops), etc. to help "jump start" the process, and to add that "next trophic level" to your burgeoning food web. 

In a perfect world, you'd allow the tank to "run in" for a few weeks, or even months if you could handle it, before adding your fishes- to really let these organisms establish themselves. And regardless of how you allow the "biome" of your tank to establish itself, don't go crazy "editing" the process by fanatically removing every trace of detritus or fragmented botanicals.

When you do that, you're removing vital "links" in the food chain, which also provide the basis for the microbiome of our aquariums, along with important nutrient processing.

So, to facilitate these aquarium food webs, we need to avoid going crazy with the siphon hose! Simple as that, really!

Yeah, the idea of embracing the production of natural food sources in our aquariums is elegant, remarkable, and really not all that surprising. They will virtually spontaneously arise in botanical-style aquariums almost as a matter of course, with us not having to do too much to facilitate it.

It's something that we as a hobby haven't really put a lot of energy in to over the years. I mean, we have spectacular prepared foods, and our understanding of our fishes' nutritional needs is better than ever.

Yet, there is something tantalizing to me about the idea of our fishes being able to supplement what we feed. In particular, fry of fishes being able to sustain themselves or supplement their diets with what is produced inside the habitat we've created in our tanks!

 

A true gift from Nature. 

I think that we as botanical-style aquarium enthusiasts really have to get it into our heads that we are creating more than just an aesthetic display. We need to focus on the fact that we are creating functional microcosms for our fishes, complete with physical, environmental, and nutritional aspects.

Food production- supplementary or otherwise- is something that not only is possible in our tanks; it's inevitable.

I firmly believe that the idea of embracing the construction (or nurturing) of a "food web" within our aquariums goes hand-in-hand with the concept of the botanical-style aquarium. With the abundance of leaves and other botanical materials to "fuel" the fungal and microbial growth readily available, and the attentive husbandry and intellectual curiosity of the typical "tinter", the practical execution of such a concept is not too difficult to create.

We are truly positioned well to explore and further develop the concept of a "food web" in our own systems, and the potential benefits are enticing! 

Work the web- in your own aquarium!

Stay curious. Stay observant. Stay creative. Stay diligent. Stay open-minded...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

 

The natural "intangibles" of botanical materials

Even with the exploding popularity of botanical-style aquariums, I still receive many questions from hobbyists unfamiliar with our practice, asking what the purpose or benefit is of utilizing these materials  in our tanks. I find myself repeating the mantra that this is not purely an aesthetic statement.

Utilizing natural botanical materials in our aquariums is not an aquascaping style; rather, it's a methodology for creating and managing a biologically diverse closed aquatic ecosystem.

There is also something very different about the way that our fishes behave when they are living in an environment which has an abundance of natural materials present.

I know, it sounds a bit weird, but it's true! We receive lots of comments about this. It's sort of an "intangible" that comes with using them in our tanks. And I suppose it makes a lot of sense, as the fishes are utilizing them much as they do in their wild habitats, for shelter, grazing, and spawning. 

Now sure, in a tank devoid of natural materials like botanicals, fishes will utilize whatever materials are available to shelter among, graze, and even spawn (hello, "spawning cones" and cracked flower pots!). Yet, there is a certain "something" that's different when you use botanicals. You can just see it.

Of course, with botanical materials, you have the added benefit that they are natural materials, consisting of substances like lignin, and they can impart other compounds stored in their tissues, such as tannin and humic substances, into the surrounding water column. And many fishes feed directly on the botanicals themselves, or remove "biocover" from their surfaces.

 

Yeah, think about it:

The texture and chemical composition of the botanicals' exteriors is really well-suited for the recruitment and growth of biofilms and fungal populations- important for the biological diversity and "operating system" of the aquarium, as we've talked about numerous times here. This is such an easily overlooked benefit of using natural materials in the aquarium.

And of course, as we know, terrestrial botanical materials, when submerged in water for extended periods of time, decompose. If there is one aspect of our botanical-style aquariums which fascinates me above almost anything else, it's the way they facilitate the natural processes of life- specifically, decomposition.

Decomposition is fundamental to the botanical style aquarium.

We use this term a lot around here...What, precisely does it mean?

de·com·po·si·tion- dēˌkämpəˈziSH(ə)n -the process by which organic substances are broken down into simpler organic matter.

A very apt descriptor, if you ask me! 

We add leaves and botanicals to our aquariums, and over time, they start to soften, break up, and ultimately, decompose. Decomposition of leaves and botanicals not only liberates the substances contained within them (lignin, organic acids, and tannins, just to name a few) into the water- it serves to nourish bacteria, fungi, and other microorganisms and crustaceans, facilitating basic "food web" within the botanical-style aquarium, just like it does in Nature- if we allow it to!

 

PVC pipe sections, flower pots, and plastic plants can't do THAT!

Utilizing botanical materials and leaves in your tank, and leaving them in until they fully decompose is as much about your aesthetic preferences as it is long-term health of the aquarium.

It's a decision that each of us makes based on our tastes, management "style", and how much of a "mental shift" we've made into accepting the transient nature of materials in a botanical-style aquarium and its function. There really is no "right" or "wrong" answer here. It's all about how much you enjoy what happens in Nature versus what you can control in your tank. Nature will utilize them completely, as she does in the wild.

I tend to favor Nature, of course. But that's just me.

And of course, we can't ever lose sight of the fact that we're creating and adding to a closed aquatic ecosystem, and that our actions in how we manage our tanks must map to our ambitions, tastes, and the "regulations" that Nature imposes upon us.

Yes, anything that you add into your aquarium that begins to break down is bioload.

Everything that imparts proteins, organics, etc. into the water is something that you need to consider. However, it's always been my personal experience and opinion that, in an otherwise well-maintained aquarium, with regular attention to husbandry, stocking, and maintenance, the "burden" of botanicals in your water is surprisingly insignificant.

Even in test systems, where I intentionally "neglected" them by conducting sporadic water exchanges, once I hit my preferred "population" of botanicals (by buying them up gradually), I have never noticed significant phosphate or nitrate increases that could be attributed to their presence.

Understand that the process of decomposition is a fundamental, necessary function that occurs in our aquariums on a constant basis, and that botanicals are the "fuel" which drives this process. Realize that in the botanical-style aquarium, we are, on many levels, attempting to replicate the function of natural habitats- and botanical materials are just part of the equation.

And of course, these botanical materials not only offer unique natural aesthetics- they offer enrichment of the aquatic habitat through their release of tannins, humic acids, vitamins, etc. as they decompose- just as they do in Nature.

Leaves and such are simply not permanent additions to our 'scapes, and if we wish to enjoy them in their more "intact" forms, we will need to replace them as they start to break down. This is not a bad thing. It just requires us to "do some stuff" if we are expecting a specific aesthetic. 

This is very much replicates the process which occur in Nature, doesn't it? Stuff like seed pods and leaves either remains "in situ" as part of the local habitat, or is pushed downstream by wind, current, etc. - and new materials continuously fall into the waters to replace the old ones.

Pretty much everything we do in a botanical-style blackwater aquarium has a "natural analog" to it! 

Despite their impermanence, these materials function as diverse harbors of life, ranging from fungal and biofilm mats, to algae, to micro crustaceans and even epiphytic plants. Decomposing leaves, seed pods, and tree branches make up the substrate for a complex web of life which helps the fishes that we're so fascinated by flourish.

Intangibles? Perhaps. Yet, highly beneficial and consequential ones, indeed.

Stay persistent. Stay bold. Stay consistent. Stay observant...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

 

 

The mystique of the "salty cichlid", the Orange Chromide

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.

Euryhaline.

Damn, we've heard that term before, haven't we?

eu·ry·ha·line (yo͝or′ə-hā′līn′, -hăl′īn′) adj.Capable of tolerating a wide range of salt water concentrations. Used of an aquatic organism.

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.

It sucks.

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?

Neat stuff.

Want a final bit of unusual trivia on this fish?

They're cleaners!

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.

 

Scott Fellman

Tannin Aquatics 

 

 

 

Stuff we've been told to fear...

A couple of days back, I was chatting with a fellow hobbyist who wanted to jump in to something a bit different within the aquarium hobby, but was afraid of the possible consequences-both socially and in his aquariums. He feared criticism from "them", and that just froze him. I felt bad that he was so afraid of criticism from others should he question the "status quo" within the hobby.

Perhaps my story might be helpful to you if you're afraid of such criticisms. 

For generations, we've been told in the aquarium hobby that we need to be concerned about the appearance of all kinds of stuff in our tanks, like algae, detritus, and "biocover".

For some strange reason, we as a hobby group seems emphasize stuff like understanding some biological processes, like the nitrogen cycle, yet we've also been told to devote a lot of resources to siphoning, polishing, and scrubbing our tanks to near sterility.

It's a strange dichotomy.

I remember the first few botanical-style tanks I created, almost two decades ago now, would hit that phase early on when biofilms  and fungal growths began to appear, and I'd hear my friends telling me, "Yeah, your tank is going to turn into a big pile of shit. Told you that you can't put that stuff in there."

Because that's what they've been told. The prevailing mindset in the hobby was that the appearance of these organisms was an indication of an unsuitable aquarium environment.

Anyone who's studied basic ecology and biology understands that the complete opposite is true. The appearance of these valuable life forms is an indicator that your aquatic environment is ideal to foster a healthy, diverse community of aquatic organisms, including fishes!

Exactly like in Nature.

I remember telling myself that this is what I knew was going to happen. I knew how biofilms and fungal growths appear on "undefended" surfaces, and that they are essentially harmless life forms, exploiting a favorable environment. I knew that fungi appear as they help break down leaves and botanicals. I knew that these are perfectly natural occurrences, and that they typically are transitory and self-limiting to some extent.

Normal for this type of aquarium approach. I knew that they would go away, but I also knew that there would be a period of time when the tank might look like a big pool of slimy shit. Or, rather, it'd look like a pile of slimy shit to those who weren't familiar with these life forms, how they grow, and how the natural aquatic habitats we love so much actually function and appear!

To reassure myself, I would stare for hours at underwater photos taken in the Amazon region, showing decaying leaves, biofilms,and fungi all over the leaf litter. I'd read the studies by researchers like Henderson and Walker, detailing the dynamics of leaf litter zones and how productive and unique they were.

I'd pour over my water quality tests, confirming for myself that everything was okay. It always was. And of course I would watch my fishes for any signs of distress...

I never saw them.

I knew that there wouldn't be any issues, because I created my aquariums with a solid embrace of basic aquatic biology; an understanding that an aquarium is not some sort of underwater art installation, but rather, a living, breathing microcosm of organisms which work together to create a biome..and that the appearance of the aquarium only tells a small part of the story.

 

I knew that this type of aquatic habitat could be replicated in the aquarium successfully. I realized that it would take understanding, trial and error, and acceptance that the aquariums I created would look fundamentally different than anything I had experienced before.

 

I knew I might face criticism, scrutiny, and even downright condemnation from some quarters for daring to do something different, and then for labeling what most found totally distasteful, or have been conditioned by "the hobby" for generations to fear, as simply  "a routine part of the process."

It's what happens when you venture out into areas of the hobby which are a bit untested. Areas which embrace ideas, aesthetics, practices, and occurrences which have existed far out of the mainstream consciousness of the hobby for so long. Fears develop, naysayers emerge, and warnings are given.

Yet, all of this stuff- ALL of it- is completely normal, well understood and documented by science, and in reality, comprises the aquatic habitats which are so successful and beneficial for fishes in both Nature and the aquarium. We as a hobby have made scant little effort over the years to understand it. And once you commit yourself to studying, understanding, and embracing life on all levels, the world of natural, botanical-style aquariums and its untapped potential opens upon to you.

Mental shifts are required. Along with study, patience, time, and a willingness to look beyond hobby forums, aquarium literature, and aquascaping contests for information. A desire to roll up your sleeves, get in there, ignore the naysayers, and just DO.

Don't be afraid of things because they look different, or somehow contrary to what you've heard or been told by others is "not healthy" or somehow "dangerous." Now sure, you can't obey natural "laws" like the nitrogen cycle, understanding pH, etc. 

You can, however, question things you've been told to avoid based on superficial explanations based upon aesthetics.

Mental shifts.

Stuff that makes you want to understand how life forms such as fungi, for example, arise, multiply, snd contribute to the biome of your aquarium. 

Let's think about fungi for a minute...a "poster child" for the new way of embracing Nature as it is.

Fungi reproduce by releasing tiny spores that then germinate on new and hospitable surfaces (ie, pretty much anywhere they damn well please!). These aquatic fungi are involved in the decay of wood and leafy material. And of course, when you submerge terrestrial materials in water, growths of fungi tend to arise. Anyone who's ever "cured" a piece of wood for your aquarium can attest to this!

Fungi tend to colonize wood because it offers them a lot of surface area to thrive and live out their life cycle. And cellulose, hemicellulose, and lignin, the major components of wood and botanical materials, are degraded by fungi which posses enzymes that can digest these materials! Fungi are regarded by biologists to be the dominant organisms associated with decaying leaves in streams, so this gives you some idea as to why we see them in our aquariums, right?

And of course, fishes and invertebrates which live amongst and feed directly upon the fungi and decomposing leaves and botanicals contribute to the breakdown of these materials as well! Aquatic fungi can break down the leaf matrix and make the energy available to feeding animals in these habitats. And look at this little gem I found in my research:

"There is evidence that detritivores selectively feed on conditioned leaves, i.e. those previously colonized by fungi (Suberkropp, 1992; Graca, 1993). Fungi can alter the food quality and palatability of leaf detritus, aecting shredder growth rates. Animals that feed on a diet rich in fungi have higher growth rates and fecundity than those fed on poorly colonized leaves. Some shredders prefer to feed on leaves that are colonized by fungi, whereas others consume fungal mycelium selectively..."

"Conditioned" leaves, in this context, are those which have been previously colonized by fungi! They make the energy within the leaves and botanicals more available to higher organisms like fishes and invertebrates! 

The aquatic fungi which will typically decompose leaf litter and wood are the group known as “aquatic hyphomycetes”. Another group of specialists, "aero-aquatic hyphomycetes," colonize submerged plant detritus in stagnant and slow- flowing waters, like shallow ponds, puddles, and flooded forest areas. Fungal communities differ between various environments, such as streams, shallow lakes and wetlands, deep lakes, and other habitats such as salt lakes and estuaries.

And we see them in our own tanks all the time, don't we? Sure, it's easy to get scared by this stuff...and surprisingly, it's even easier to exploit it as a food source for your animals! We just have to make that mental shift... As the expression goes, "when life gives you lemons, make lemonade!"

 

I knew when I started Tannin  that I had to "walk the walk." I had to explain by showing my tanks, my work, and giving fellow hobbyists the information, advice, and support they needed in order to confidently set out on their own foray into this interesting hobby path.

I'm no hero. Not trying to portray myself as a visionary.

The point of sharing my personal experience is to show you that trying new stuff in the hobby does carry risk, fear, and challenge, but that you can and will persevere if you believe. If you push through. IF you don't fear setbacks, issues, criticisms from naysayers.

You have to try. In my case, the the idea of throwing various botanical items into aquariums is not my invention. It's not a totally new thing. People have done what I've done before. Maybe not as obsessively or thoroughly presented (and maybe they haven't built a business around the idea!), but it's been done many, many times.

The fact is, we can and should all take these kinds of journeys.

Stay the course. Don't be afraid. Open your mind. Study what is happening. Draw parallels to the natural aquatic ecosystems of the world. Look at this "evolution" process with wonder, awe, and courage.

And know that the pile of decomposing leaves, fungal growth, and detritus that you're looking at now is just a steppingstone on the journey to an aquarium which embrace nature in every conceivable way.

Stay brave. Stay curious. Stay diligent. Stay observant...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

Transitional Habitats...A new aquarium hobby frontier?

We've spent a lot of time over the least several years talking about the idea of recreating specialized aquatic systems. We've talked a lot about transitional habitats- ecosystems which alternate between terrestrial and aquatic at various times of the year.  These are compelling ecosystems which push the very limits of conventional aquarium practice. 

As you know, we take a "function first" approach, in which the aesthetics become a "collateral benefit" of the function. Perhaps the best way to replicate these natural aquatic systems inner aquariums is to replicate the factors which facilitate their function. So, for example, let's look at our fave habitats, the flooded forests of Amazonia or the grasslands of The Pantanal.

To create a system that truly embraces this idea in both form and function, you'd start the system as a terrestrial habitat. In other words, rather than setting up an "aquarium" habitat right from the start, you'd be setting up what amounts to a terrarium. Soil/sand, terrestrial plants and grasses, leaves, seed pods, and "fallen trees/branches" on the "forest floor."

 

You'd run this system as a terrestrial display for some extended period of time- perhaps several weeks or even months, if you can handle it- and then you'd "flood" the terrestrial habitat, turning it into an aquatic one. Now, I'm not talking about one of our "Urban Igapo" nano-sized tanks here- I"m talking about a full-sized aquarium this time.  

This is different in both scale and dynamic. After the "inundation", it's likely that many of the plants and grasses will either go dormant or simply die, adding other nutrient load in the aquarium.

A microbiome of organisms which can live in the aquatic environment needs to arise to process the high level of nutrients in the aquarium. Some terrestrial organisms (perhaps you were keeping frogs?) need to be removed and re-housed.

The very process of creating and populating the system during this transitional phase from terrestrial to aquatic is a complex, fascinating, and not entirely well-understood one, at least in the aquarium hobby. In fact, it's essentially a virtually unknown one. We simply haven't created all that many systems which evolve from terrestrial to aquatic.

Sure, we've created terrariums, paludariums, etc. We've seen plenty of "seasonally flooded forest" aquairums in biotope aquarium contests...But this is different. Rather than capturing a "moment in time", recreating the aquatic environment after the inundation, we're talking about recreating the process of transformation from one habitat to another.

Literally, creating the aquatic environment from a terrestrial one.

Psychologically, it would be sort of  challenging!

I mean, in this instance, you've been essentially running a "garden" for several months, enjoying it and meeting the challenges which arise, only to embark several months later on a process which essentially destroys what you've created, forcing you to start anew with an entirely different environment, and contend with all of its associated challenges (the nitrogen cycle, nutrient control, etc.)

Modeling the process. 

Personally, I find this type of approach irresistible. Not only do you get to enjoy all sorts of different aspects of Nature- you get to learn some new stuff, acquire new skills, and make observations on processes that, although common in Nature, were previously unrecorded in the aquarium hobby. 

 

You'll draw on all of your aquarium-related skills to manage this transformation. You'll deal with a  completely different aesthetic- I mean, flooding an established, planted terrestrial habitat filled with soils and plants will create a turbid, no doubt chaotic-looking aquascape, at least initially. 

 

This is absolutely analogous to what we see in Nature, by the way.Seasonal transformations are hardly neat and tidy affairs. 

Yes, we place function over form. However, that doesn't mean that you can't make it pretty! One key to making this interesting from an aesthetic perspective is to create a hardscape of wood, rocks, seed pods, etc. during the terrestrial phase that will please you when it’s submerged.

You'll need to observe very carefully. You'll need to be tolerant of stuff like turbidity, biofilms, algae, decomposition- many of the "skills"we've developed as botanical-style aquarists.You need to accept that what you're seeing in front of you today will not be the way it will look in 4 months, or even 4 weeks.

You'll need incredible patience, along with flexibility and an "even keel.”

We have a lot of the "chops" we'll need for this approach already! They simply need to be applied and coupled with an eagerness to try something new, and to help pioneer and create the “methodology”, and with the understanding that things may not always go exactly like we expect they should.

For me, this would likely be a "one way trip", going from terrestrial to aquatic. Of course, much like we've done with our "Urban Igapo" approach, this could be a terrestrial==>aquatic==>terrestrial "round trip" if you want! That's the beauty of this. You could do a complete 365 day dynamic, matching the actual wet season/dry season cycles of the habitat you're modeling.

Absolutely. 

The beauty is that, even within our approach to "transformational biotope-inspired" functional ecosystems, you CAN take some "artistic liberties" and do YOU. I mean, at the end of the day, it's a hobby, not a PhD thesis project, right?

Yeah. Plenty of room for creativity, even when pushing the state of the art of the hobby! Plenty of ways to interpret what we see in these unique ecosystems.

Habitats which transition from terrestrial to aquatic require us to consider the entire relationship between land and water- something that we have paid scant little attention to in the aquarium hobby, IMHO. 

And this is unfortunate, because the relationships and interdependencies between aquatic habitats and their terrestrial surroundings are fundamental to our understanding of how they evolve and function.

There are so many other ecosystems which can be modeled with this approach! Floodplain lakes, streams, swamps, mud holes...I could go on and on and on. The inspiration for progressive aquariums is only limited to the many hundreds of thousands of examples which Nature Herself has created all over the planet.

We should look at nature for all of the little details it offers. We should question why things look the way they do, and postulate on what processes led to a habitat looking and functioning the way it does- and why/how fishes came to inhabit it and thrive within it.

With more and more attention being paid the overall environments from which our fishes come-not just the water, but the surrounding areas of the habitat, we as hobbyists will be able to call even more attention to the need to learn about and protect them when we create aquariums based on more specific habitats.

The old adage about "we protect what we love" is definitely true here!

And the transitional aquatic habitats are a terrific "entry point"into this exciting new area of aquarium hobby work.

Stay inspired. Stay creative. Stay observant. Stay resourceful. Stay diligent...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics 

Someplace like...home?

Like so many of you, I am utterly awed by the sheer variety of tropical fish species that we've managed to breed in our aquariums over the decades. This is a testimony to the skill set and dedication of talented hobbyists and commercial breeders worldwide. And with obvious implications for some wild populations of fishes whose habitats arena danger, the idea of breeding fishes is a timely one.

Of course, there are absolutely benefits to a well-managed wild fishery, too, including protection of resources, economic benefits to indigenous peoples, and the preservation of wild populations. Programs like Project Piaba in Brazil have shown the tangible benefits to the people, environment, and the fishes that may be had with a properly-managed program of sourcing wild-caught fishes.

And, when it comes to the way we keep our fishes in the hobby on an everyday basis, I find a very interesting dichotomy here...

Have you ever thought about the way we've "domesticated" the fishes that we keep in our aquariums? I mean, the way we have sort of categorically "made" fishes more accommodating of the environmental conditions that we would like to provide them with in our aquariums? For example,  we've proudly advertised that fishes like Discus don't require soft, acidic water to thrive and reproduce. In fact, a number of breeders spawn and rear them in harder, more alkaline conditions.

This is interesting and makes me think about this from multiple angles...good and bad.

As you know, I tend to spend a fair amount of time snooping around the scientific literature online, looking for tidbits of information that might fit nicely into our fascination and evolving technique with natural blackwater and brackish- aquariums.

It's a pretty fun, albeit geeky- pastime, really- and quite educational, too!

And one of the interesting things about sifting through much of the scientific stuff is that you can occasionally find bits and pieces of information which may not only confirm a "hunch" that you have had about something- these data can sometimes send you into an entirely new direction! (I know that it can, lol!)

As a lover of brackish-water habitats, I've spent a lot time over the years researching suitable fishes and other aquatic organisms from this environment for aquarium keeping. I've made a lot of interesting discoveries about brackish water habitats and the fishes which supposedly occur in them. 

Notice I use the term "supposedly..?"

Interestingly, many of the fishes that we in the hobby have assigned the "brackish" moniker to are actually seldom found in these types of habitats. Perhaps some small populations of some of these fishes might be from mildly brackish environments, but many of them are primarily found in pure freshwater.

Perhaps through a combination of misinformation, assumption, and successful practice by a few hobbyists over the years, we've sort of attached the "brackish water fish" narrative to them in general.

Now, sure, many fishes can adapt to brackish water conditions, but I'm more fascinated by the fishes which are actually found naturally in these environments. And it's always interesting when you can find out that a fish which you have previously dismissed as not having typically come from this environment actually does come from it naturally!

It's like a little discovery!

One of those happy "surprises" is our good friend, the "Endler's Livebearer", Poceilia wingei. Many of you love this fish and keep it extensively. 

This popular fish is widely kept under "typical livebearer conditions" in the aquarium ( higher pH and harder water).

However, there are a number of wild populations form their native Venezuela which inhabit mildly brackish water coastal lagoons and estuaries, for example, Laguna de los Patos, near Cumana, which has definite ocean influence, although it is far less salty than researchers thought it may have been in the past. And the wild populations residing there might very well be considered "endangered", or at least, limited.

Now, this kind of stuff is not "revolutionary" from a hobby standpoint, as it seems like we've known this for some time. And although the fish are very adaptable, we don't hear all that much about keeping them in what we'd call "brackish" conditions (like typically SG of 1.003-1.005, although I like to push it a bit higher, lol). It's just interesting to ponder and kind of get your head around.

And with all of the popularity of this fish, it seems to me like the brackish water habitat for this species has not been embraced much from a hobby standpoint.

And I suppose it makes sense- it's far easier to simply give fishes harder, alkaline water than to "mess with adding salt" to their tanks for a lot of hobbyists. In addition, wild populations of these fishes are scant, as is natural habitat data, so indeed confirming with any great certainty that they are even still occurring in these types of habitats is sketchy.

And often, so-called 'populations" of fishes in these specialized habitats might have been distributed as a result of actions by man, and are not even naturally occurring there- further confounding things!

In general, the question about adding salt to livebearer tanks has been debated for a long time, and there are many views on the subject. Obviously, the ultimate way to determine if you should or should not add salt to an Endler's or other livebearer tank would be to consider the natural habitats of the population you're working with.

 

Easier said than done, because  the vast majority of them are now commercially or hobbyist bred for generations- especially Endler's- and wild collection data is not always easy to obtain.

I think the debate will go on for a long time!

Yet, with the increasing popularity of brackish water aquariums, we're hoping to see more experiments along this line for many different species! I was recently very happy to secure some specimens of the miserably-named "Swamp Guppy", Micropoceilia picta, a fish which absolutely does come from brackish water. And I have no intention of ever "adapting" them to environmental conditions which are more "convenient" for us hobbyists!

Now, you know I've always been a fan of sort of "re-adapting" or "re-patriating" even captive-bred specimens of all sorts of fishes (like "blackwater-origin" characins, cichlids, etc.) to more "natural" conditions (well, "natural" from perhaps a few dozen generations back, anyhow). I am of the opinion that even "domesticated" fishes can benefit from providing them with conditions more reminiscent of those from the natural habitats from which they originated.

Although I am not a geneticist or biological ethicist, I never will buy into the thought that a few dozen captive generations will "erase" millions of years of evolutionary adaptation to specific habitats, and that re-adapting them to these conditions is somehow "detrimental" to them. Something just seems "off" to me about that thinking.

I just can't get behind that.

Now, even more compelling "proof" of that it's not so "cut-and-dry" is that many of the recommended "best practices" of breeding many so-called "adaptable" species are to do things like drop water temperatures, adjust lighting, or perform water exchanges with peat-influenced water, etc....stuff intended to mimic the conditions found in the natural habitats of the fishes...

I mean...WTF? Right? 

Like, only give the fishes their "natural" conditions when we want to breed them? Really? That mindset just seems a bit odd to me...

Of course, there are some fishes for which we don't really make any arguments against providing them with natural-type environmental conditions, such as African rift lake Cichlids.

I find this absolutely fascinating, from a "hobby-philosopher" standpoint!

And then, there are those fishes which we have, for various reasons (to minimize or prevent the occurrence of diseases) arbitrarily decided to manipulate their environment deliberately away from the natural characteristics under which they evolved for specific reasons. For example, adding salt to the water for fishes that are typically not known to come from brackish habitats.

Examples are annual Killifishes, such as Nothobranchius, which in many cases don't come from brackish environments naturally, yet we dutifully add salt to their water as standard practice. The adaptation to a "teaspoon of salt per gallon" or so environment is done for prophylactic reasons, rather than what's "convenient" for us- a rather unique case, indeed...and again, something that I find fascinating to look at objectively.

Is salt simply the easiest way to prevent parasitic diseases in these fishes, or are there other ways which don't require such dramatic environmental manipulations?

And then, of course, there are those unexpected populations of fishes, like various Danios and Gold Tetras, for example, which are found in mildly brackish conditions...Compelling, interesting...yet we can't conclude that all Gold Tetras will benefit from salt in their water, can we?

And, as we evolved to a more sustainable hobby, with greater emphasis on captive -bred or carefully-sourced wild fishes, and as more wild habitats are damaged or lost, will we also lose valuable data about the wild habitats of the fishes we love so much?  

Data which will simply make the "default" for many fishes to be "tap water?"

I hope not.

Is it possible, though, that we've been so good at "domesticating" our fishes to our easier-to-provide tap water conditions- and our fishes so adaptable to them- that the desire to "repatriate" them to the conditions under which they've evolved is really more of a "niche" thing for geeky hobbyists, as opposed to a "necessary for success" thing?

I mean, how many Discus are now kept and bred exclusively in hard, alkaline water- markedly different than the soft, acid blackwater environmental conditions under which they've evolved for eons? Am I just being a dreamer here, postulating without hard data that somehow the fishes are "missing something" when we keep and breed them in conditions vastly different than what the wild populations come from?

Do the same genetics which dictate the color patterns and fin morphology also somehow "cancel out" the fish's "programming" which allows them to be healthiest in their original native conditions?

How do we reconcile this concept?

In the end, there are a lot of variables in the equation, but I think that the Endler's discussion is just one visible example of fishes which could perhaps benefit from experimenting with "throwback" conditions. I'm by no means anything close to an expert on these fish, and my opinions are just that- opinions. Commercially, it may not be practical to do this, but for the hobbyist with time, resources, and  inclination, it would be interesting to see where it takes you.  

Like, would the same strain kept in both brackish and pure freshwater habitats display different traits or health characteristics?

Would there even be any marked differences between specimens of certain fishes kept under "natural" versus "domesticated" conditions? Would they show up immediately, or would it become evident only after several generations? And again, I think about brackish-water fishes and the difficulty of tracing your specimens to their natural source, which makes this all that much more challenging!

I look forward to many more such experiments- bringing natural conditions to "domesticated" fishes, and perhaps unlocking some more secrets...or perhaps simply acknowledging what we all know:

That there truly is "no place like home!"

Stay observant. Stay curious. Stay adventurous. Stay resourceful. Stay experimental. Stay relentless...

And Stay Wet.

 

Scott Fellman

Tannin Aquatics