April 13, 2022


Working with "the establishment!"

The last few pieces we've shared here on "The Tint" have apparently really resonated with a lot of you! We've received a lot of comments, questions, and thoughts about deploying patience and observation during the establishment of new botanical method aquariums. I'm very pleased to hear this, because the fact that so many people have been "buying in" to these philosophies is indicative a of a "mental shift" of sorts in our hobby movement.

As I've said numerous times here, botanical method aquariums are not an "aquascaping style"- they are a representative of a methodology which embraces natural materials and processes to "finish" what we start- to not only help create and enrich the ecosystem- but to change the aesthetics as it does.

This "handing off" to Nature to take over what we've started in the earliest days of our tanks is a hugely important step in what we do. In fact, I dare say that this is a foundational part of our approach. I can't stress it enough. And honestly, I admit that it's really hard to do sometimes. You've earnestly done the work to get your new aquarium up and running, and then it starts getting a bit turbid and tinted, and biofilms and fungal growths start appearing- and we tell you to "keep your hands" out and just...enjoy!

For those patient souls who admire and appreciate the process of Nature, and therefore embrace the aesthetics as the aquarium establishes itself, it's a time to savor all that is unfolding. For those who are perhaps a little less patient, maybe unsure, and eager to see clear (but tinted) water and perhaps a less "disheveled" start to their new tank, it can test their patience and faith in the approach for sure!

Interestingly, one of the most frequently asked questions that we receive about newly established botanical method tanks is how to get them to look "broken in" and "established" more quickly! 

Okay, let me be clear about a few things. I don't advocate circumventing the processes which help establish our botanical method aquariums. I do, however, understand that many enjoy the "look" of these tanks, and want to enhance the aesthetic experience whenever possible.

The strange inconsistency is that it would be better to embrace the aesthetics which arise when we create these types of tanks. So my advice on how to get the "look" you like is to go "all-in" and embrace the extensive use of the materials which we use to create them.

Of course, there are a few things you could do to sort of "expedite" the "established" look of a botanical-method tank, but they're really just sort of "hacks" (ugh I hate that word!)- and are no substitutes for just letting a tank evolve over time naturally.

"Well, what are they, Fellman?" 

So you could use some botanicals and partially decomposed leaf litter, substrate, and even water from an established botanical-method tank to give you a bit more of an "evolved" vibe and definitely some microbial populations and therefore, some function. This is completely consistent with the concept of adding sand from an established, healthy aquarium, which has been used by aquarists for decades. 

And, if doing this for purely "functional" reasons as opposed to just trying to "hack" the "look"- I can actually see tremendous merit to this idea. Hell, adding sand or gravel/decomposing leaves and such from an established tank to "jump-start" a new one has been standard practice in marine aquariums for decades, and in freshwater as well.

Doing this with botanical materials- rich with detritus, biofilms, fungal growth, and beneficial bacteria- is simply the botanical-style version of this time-honored process, right? It makes perfect sense.


Yet, there is no substitute for patience and the passage of time.

Looking back on some of my favorite tanks that I've executed in the past few years, even though they look awesome from the start, it becomes increasingly obvious to all that these systems really don't hit that complete "look and feel" that we expect until long after they have evolved naturally...however long that is.

Stuff needs to acquire a "patina" of biofilm, a "stain" from the tannins, and decomposition of botanical materials needs to really begin before one of these systems turns "functional" as well. 

It takes time. Fungal growths establish. Bacterial populations grow. 

Every new botanical-style tank looks cool from day one...A lot of people love the clean and fresh-looking leaves, and seed pods that are squeaky clean. More and more of of us love the look of softening and decomposing leaves and botanicals. And yet, the long-established systems are the ones that really stand out.

After 6 months, that's when things get really special.


That's when the bulk of the "settling in" is done. The bacterial, fungal, and microorganism populations have increased, and nutrient imports and exports have balanced out and stabilized. The tank looks great, smells earthy and pleasant, the substrate is rich and ecologically diverse, and the fishes take on a very relaxed demeanor.

I've long held that my fave botanical-style, blackwater aquarium of all was the one I did about 3 years ago..an aquarium utilizing mangrove wood, extensive leaf litter, and catappa bark throughout. This is probably the only tank in recent years that I've truly regretted changing and moving on from! 😂 

And it wasn't all sexy and dark and established-looking from the get-go.


It literally looked like shit for the first couple of months of it's existence: Slightly tinted water, a contrived-looking "campfire-like" wood stack, bare sand, and mostly intact botanical materials. I had to do a bunch of iterations with the hardscape to get it where I wanted it. It almost looked contrived, but I knew from experience that if I waited it out, let Nature do Her thing- that the potential was huge in this tank.

However, a few months in, biofilms started forming. The wood acquired that "patina" we talk about so much. Leaves and botanicals broke down...And the water took on the most earthy-looking, deeply mysterious color I've seen in a blackwater aquarium. A very slight "turbidity" or "flavor" as one of my friends called it- that was as compelling as it was beautiful.

Yeah, by some standards, the water in the tank could be described as almost "turbid"- taking on an appearance as though there were fine materials in the water column. Yet, the tank had a real magical appearance with the LED lighting; the fishes were as colorful, relaxed and happy as any I've ever seen, and the water parameters were spot-on and consistent for as long as the tank was set up. IN fact, I had three spawns of Rummy Nose Tetras in that tank!

This tank had a certain "something":

The essence "wabi-sabi", for sure. Transience, the ephemeral aspects of our botanicals...the wonders of Nature, embraced.

In Nature, many habitats go through periods of time where they are inundated by a flow of sediments, detritus, etc., and this has a big impact not only on how they function and support the life forms which reside in them, but in how they look as well.

This is very analogous to the way in which our botanical method aquariums "break in" and establish themselves that it's not even funny! Many of the same ecological and hydrological processes which impact wild habitats appear to shape our botanical method tanks at home, too.

And it is part of a sequence. A pattern...A journey. Perhaps what could best be called an evolution- which Nature has carefully set up and managed over eons. 

In our own aquarium work, we can replicate this sequence and process...it's not that hard to do. The really difficult part is the waiting. Acquiring the patience that we must deploy as we watch our aquariums evolve, uninterrupted- under the steady hand of Nature.

That's the magic.

It's a process- the part of the journey which every botanical-method aquarist needs to embrace and understand. And sure, if you can accept the "look" during the "establishment phases"-  

Of course, an aquarium which utilizes botanicals as a good part of its hardscape follows a set of phases, too. And I've found that once a botanical method aquarium (blackwater or brackish) hits that sort of "stable mode", it's just that- stable. You won't see wildly fluctuating pH levels, increasing nitrates, phosphates, etc. To a certain degree, the aquarium has achieved some sort of "biological equilibrium."

Now, one thing that's unique about the botanical method approach is that we tend to accept the idea of decomposing materials accumulating in our systems. We understand that they act, to a certain extent, as "fuel" for the micro and macrofauna which reside in the aquarium. The idea of leaving this material in place over the long-term is a crucial component of this approach, IMHO.

When we do that- when we make those mental shifts and accept that our aquariums aren't really "finished" in 5 days- or 50- we have suddenly begun to understand this whole "botanical-method aquarium thing."

Suddenly, the day-to-day appearance of the aquarium during its establishment phase is not something which you "endure"- it becomes an intriguing part of the journey. Yeah, a mental shift of the highest order- appreciating your aquarium during every phase of its existence.

That's how you work with "the establishment..."

Stay strong. Stay committed. Stay creative. Stay bold...

And Stay Wet.


Scott Fellman

Tannin Aquatics  

April 08, 2022


"Walking away." A study in Mental Toughness.

We ask a lot of ourselves in the botanical method aquarium approach. We ask you to embrace a completely different aesthetic. We ask you to accept natural processes of fungal colonization, biofilm recruitment, and decomposition. We ask you to tolerate turbid water, and a deep brown tint.

It's a big "ask."

When you start a botanical method aquarium, you set it up in such a way as to create optimum conditions for a natural aquatic ecosystem to evolve. And once you set those conditions, you sort of "walk away" for a while. 


There is a point when you're like, "Oh, I really like this hardscape"- and you set in your initial botanicals...and then you sort of just "walk away" and let it evolve for a bit. 

A "jumping-off" stage, where our initial work is done, and Nature takes over for a while, breaking down the botanicals, allowing a "patina" of fungal growth and biofilm to cover some of the surfaces, removing the crisp, harsh, "new" feeling.  This is where Amano's concept of embracing the Japanese philosophy of wabi-sabi takes over. Accepting the transient nature of things and enjoying the beauty of the changes that occur over time.

And of course, once stuff starts "softening" or breaking down, it doesn't mean that your job is done, or that you're just a passive observer from that point on. Nope. It means that you're now in a cool phase of "passively managing" (and by "managing", I am emphasizing observation more than "intervening!") the aquarium.

I personally feel that THIS phase is the most exciting and rewarding part of the whole process!  And perhaps- one of the most "natural..".

A phase when you interact with your aquarium on a very different level; a place where you get to play a role in the direction your tank is going, without constantly interrupting the natural progression taking place within the little microcosm you created!

You're allowing Nature to do what it's done for eons in the wild aquatic habitats of the world; to build up an ecosystem, utilizing the materials present in the local environment. A transformation of sorts, from seemingly lifeless and barren to rich and brimming with life.

And of course, the natural "analog" of this phase is when those initial rains arrive and inundate formerly dry habitats, flooding forests and grasslands, transforming them into aquatic habitats once again. The sort of "pause" between storms gives life a chance to make those adjustments necessary during the transformation.

To get there, your aquarium has to "go through some things." You'll need to endure some aesthetic challenges, such as turbidity, the formation of stringy biofilms and fungal growths, and the decomposition of botanical materials.

If you're like me, and you utilize fine sediments in your tank as part of the substrate, one of the things you need to deal with is cloudy water for a week or two- right off the bat. This freaks a lot of people out. As aquairum hobbyists, we've been indoctrinated to expect crystal clear water, vibrantly clean sand, crisp green plants, and lots of happy fishes as the absolute barometer of success.

The idea of waiting for weeks or even months before you achieve some aesthetically different result is not only alien to most hobbyists, it seems downright antithetical to our hobby culture.

Yet, by enduring, waiting, observing, and persevering as your aquarium establishes and sorts itself out naturally, you're going to end up with a result that is far more satisfying, pleasing, and overall more successful, IMHO.

It takes a certain mental strength to walk away from your newly set up aquarium for a while and let it do its thing. By walking away, I don't mean simply ignoring your tank, of course. What I mean is that you're taking a more "hands off" approach and not constantly interfering as your aquarium goes through its earliest phases. 

You're not going to get a whole lot of sympathy from fellow aquarists while your tank goes through this phase. You'll receive a lot of "I told you so!" type comments, or rhetorical questions/statements, like, "Why would you do it that way in the first place? You had to know this would happen!" (as if this is the final product!) 

Vast swaths of the aquarium hobby are adherent to an attitude of impatience and a "joiner" mentality, eagerly trying to recreate what they see on Instagram. They simply won't understand why you've elected to take a path that takes you though what they would describe as a self-inflicted "aesthetic purgatory" for some protracted period of time! They'd rather be diligently scrubbing their "Ohiko Stone" or "Black Mountain Wood" or whatever is trendy, and enjoy their sterile interpretation of Nature.

Good for them.

You're on a different path.

You have a dramatically different goal, and employ a completely different mindset. You have something that they utterly lack- wether they care to say it or not- patience...and a certain mental toughness. These are "soft skills" in the aquairum hobby that no one really likes to talk about, other than to do the obligatory "lip service" thing about employing patience in some superficial manner. ("Oh, you need to be really patient to get your Iwagumi layout just right...").

We're talking about deploying patience as your miniature closed ecosystem establishes itself in your aquarium! That's on a totally different level, and requires real patience, not buzzword, "Insta-quote ready" bullshit.

DO you have it? Do you want it?

It's okay of you don't; not everyone feels it's of value. A lot of people don't share your enthusiasm for the process, or a desire to go through a slower period of tank establishment. It's okay. A lot of these people will offer you "fixes" for your "problem"- because that's how they see anything which deviates from the "norm" which they so fervently adhere to. Some will out right trash you for your "ignorance."

And, when they're busy shitting on what you're doing because it's "not what everyone who's 'successful' does", I sort of think that it's time to acquire this kind of patience, don't you? If for no other reason than to demonstrate that there is more than one path to "success" in the hobby. And besides, you're a hell of a lot more intrigued by what Nature does with natural materials than you are with the work that some other hobbyist does, right?

Watching a display aquarium evolve and sort of "find itself" naturally over time is proving to be one of the most enjoyable discoveries I've made in the hobby in decades. By simply following established maintenance routines, and monitoring what's occurring in the tank, as opposed to constantly trying to "pre-empt" problems, I've had more stability, more growth...more success than ever before.

Accepting that there is most definitely a "dance" in our aquariums, and becoming an "active monitor" instead of an "active intervener" has added a new and rewarding aspect to my love of the hobby.

I think that it not only makes you a more engaged hobbyist, it gives you a remarkable appreciation for the long term evolution of an aquarium; an appreciation for the pace by which Nature operates, and the direction which your aquarium goes.

It all starts with an idea...and a little bit of a "waiting game..." and a belief in Nature; a trust in the natural processes which have guided our planet and its life forms for eons. 

The appreciation of this process is a victory, in and of itself, isn't it? The journey- the process- is every bit as enjoyable as the destination, I should think.

It just requires a little mental toughness...and patience.

Stay tough. Stay engaged. Stay creative. Stay patient...

And Stay Wet.


Scott Fellman

Tannin Aquatics


Heading to the bottom...Again!

Time to hit on another of my fave topics regarding botanical method aquariums; one that we've talked about before- yet one that is still new and exciting to many of us, and perhaps clouded at times with a lot of misinformation, too.

We're talking about botanically-supplemented substrates!

For far too long in the aquarium hobby, I think that we've treated aquairum substrates as simply an afterthought. I mean, there are all sorts of sands and gravels on the market today, but I think that we sort of take them for granted- or at the very least, we treat them as a "requirement" when setting up a tank, and move on to other, more "exciting stuff": "Sand added, check. Time to select the wood!"

That sort of thing.

One of the most "liberating" things we've seen in the botanical-method aquarium niche is our practice of utilizing the bottom itself to become a feature aesthetic point in our aquariums, as well as a functional mechanism for the inhabitants.

"Oh, shit, he's talking about that 'functional aesthetic' thing again!"

Yeah. Yes I am. 😎

Because I think that there are a lot of "missed opportunities" to do something cool with substrates in our tanks. Opportunities to make it a much more important part of the aquarium. 

When you look at it from our rather biased perspective, and from a strictly aesthetic sense, the bottom itself becomes a big part of the aesthetic appeal of the aquarium. You may not focus on it, observationally, but it's hugely important. And of course, I see the bottom of the aquarium as more than just sand or whatever. Rather, it's a important component of the aquarium habitat, with the botanical materials placed upon or mixed into the substrate- or, in some cases, becoming the substrate!

These materials form an attractive, texturally varied "microscape" of their own, creating color and interest. In addition to be being comprised of the usual sands and gravels, we can be adding bits of botanicals, root pieces, twigs, leaves, etc. into the mix.


Again, the focus isn't just on aesthetics. 

It's about creating a habitat for the fauna which help "run" our tanks!

Much like in Nature, the materials that we place on the bottom of the aquarium will become an active, integral part of the ecosystem. From a "functional" standpoint, bottoms comprised of supplemented with a variety of botanical materials form a sort of "in-tank refugium", which allows small aquatic crustaceans, fungi, and other microorganisms to multiply and provide supplemental food for the aquarium, as we've touched on before.

So, the idea of creating rich, diverse botanical-influenced substrates for the purpose of infusing tannins, humic substances, and other compounds- as well as creating a "matrix" for the growth and propagation of beneficial micro and microfauna is pretty appealing to me.

Using a botanically-infused substrate to create a unique, ecologically diverse, functional, and aesthetically interesting affect on the aquarium- even one that doesn't have aquatic plants in it- is a sort of different approach.

Functionality. Interest. Aesthetics. Stability. They're all there!


Nature provides no shortage of features which can provide inspiration for unique aquariums.

Think about the materials which accumulate on and in the substrates of natural aquatic habitats, and why they accumulate in the first place. Well, typically, in addition to soils and leaves, you'll see sediments, pieces of plant roots, bits of twigs and bark, and the occasional seed pod. Almost all of this material arrives in these bodies of water from the surrounding terrestrial environment.

Some of it is present on forest floors, and when nearby streams overflow, inundating the once dry floor, these materials become part of the aquatic environment, influencing both the structure and the ecology of the habitat. Other materials, like sediments, are the product of hydrology and erosion- rocks ground down over eons by water; or soils- which find their way into streams during periods of intense rain, with the resulting material distributed over vast distances by current.

The beauty of Nature is that She uses pretty much everything that is thrown at Her. Fishes and other organisms feed directly upon some of this material, or on the other life forms (small crustaceans, insects, fungal growths) which live among it. The bottom of streams and other becomes a vibrant, ecologically diverse habitat, which supports a tremendous amount of life at many levels.

And we just throw bag of aquarium sand or gravel on the bottom of our tanks...and move on!

Shit. Really?

Like, WTF is a matter with us fish geeks? There is HUGE opportunity here! We need to give a lot more thought to what goes on the bottom of our aquariums! Instead of becoming a literal "placeholder" in our tanks, substrate should become the ecological "backbone"- and a (functionally aesthetic) foundation of our miniature aquatic ecosystems- just like it is in Nature!

Now, the first "pushback" we hear from critics of this type of approach in aquariums is that it will result in all sorts of problems- ranging from suppressed pH to high levels of nitrates, or even pockets of hydrogen sulfide and other nasty stuff accumulating.

I think that this is an incredible over-reaction and grounded in not fully thinking through why we are creating substrates like this in the first place.

In Nature, the leaf litter "community" of fishes, insects, fungi, and microorganisms is really important to the overall tropical environment, as it assimilates terrestrial material into the blackwater aquatic system (and, by doing this, acts to reduce the loss of nutrients to the forest which would inevitably occur if all the material which fell into the streams was washed downstream...)

The key point: These materials foster the development of life forms which process it. Stuff is being used by life forms.

It's the same in our aquariums.

And bits of botanical materials and such not only provide a physical substrate upon which these organisms can grow and multiply as they process it- they provide a sort of "on board nutrient processing center" within the aquarium.

If you approach this "substrate enrichment" idea holistically, rather than just from some warped aesthetic mindset, creating and managing such a system is not at all difficult or dangerous. In fact, you don't really need to give it all that much thought in a well-managed aquarium, once it's set up.

I realize that experimenting with these unusual substrates requires not only a sense of adventure, a direction, and some discipline- but a willingness to accept and deal with an entirely different aesthetic than what we know and love. And this also includes pushing into areas and ideas which might make us uncomfortable, not just for the way they look, but for what we are told might be possible risks.

One of the things that many hobbyists ponder when we contemplate creating deep, botanical-heavy substrates, consisting of leaves, sediment, bark, and other botanical materials is the "buildup of hydrogen sulfide", CO2, and other undesirable compounds within the substrate.

Well, sure, I can't entirely "diss" fellow hobbyists for having this fear. It does make sense that if you have a large amount of decomposing material in an aquarium, then some of these compounds are likely to accumulate in heavily-"active" substrates. The big "bogeyman" that we all seem to zero in on in our "sum of all fears" scenarios - the one which keyboard warriors on the forums will pounce on- is an accumulation of deadly hydrogen sulfide, which results from bacterial breakdown of organic matter in the total absence of oxygen.

Let's think about this for just a second.

In a botanical bed with materials placed on the substrate, or loosely mixed into the top layers, will it all really "pack down" enough to the point where there is a complete lack of oxygen and we develop a significant amount of this reviled compound in our tanks? Are we managing tanks in such a way as to encourage no circulation whatsoever?

I think that we're more likely to see some oxygen in this layer of materials, and in fact, I can't help but speculate- and it IS just speculation- that actual de-nitirifcation (nitrate reduction), which lowers nitrates while producing free nitrogen, might actually be able to occur in a "deep botanical" bed.

And it's certainly possible to have denitrification without dangerous hydrogen sulfide levels. As long as even very small amounts of oxygen and nitrates can penetrate into the substrate this will not become an issue for most systems. I have yet to see a botanical-method aquarium where the material has become so "compacted" as to appear to have no circulation whatsoever within the botanical layer.

Now, sure, I'm not a scientist, and I base this on close visual inspection of numerous aquariums, and the basic aquarium-standard chemical tests I've run on my systems under a variety of circumstances. As one who has made it a point to keep my botanical method aquariums in operations for very extended time frames, I think this is significant. The "bad" side effects we're talking about should manifest over these longer time frames...and they just haven't.

Yeah- in my experience, based on literally a lifetime of playing with all sorts of combinations of materials in dozens and dozens of my aquariums' substrates ('cause I've always been into that stuff!), I cannot attribute a single environmental lapse, let alone, a "tank crash", as a result of such additions.

A well-managed substrate, in which uneaten food and fish feces are not allowed to accumulate to excess, and in which regular nutrient export processes are embraced, rather than decimated by constant interference (ie; siphoning) it's not an issue, IMHO. When other good practices of aquarium husbandry (ie; not overcrowding, overfeeding, etc.) are empIoyed, a botanically-"enriched" substrate can enhance- not inhibit- the nutrient processing within your aquarium and help maintain high water quality for extended periods of time.

Like many of you, I have always been a firm believer in some forms of nutrient export being employed in every single tank I maintain. Typically, it's regular water exchanges. Not "when I think about it', or "periodically", mind you.

Nope, it's weekly. 

Now look,  I'm not saying that you can essentially disobey all the common sense husbandry practices we've come to know and love in the hobby (like not overcrowding/overfeeding, etc.) and just change the water weekly and everything's good. And I'm not suggesting that the only way to succeed with adding botanical materials to the substrate is to employ massive effort at nutrient export; the system otherwise teetering on a knife's edge, with disaster on one side and success on the other. 

It's not that binary. 

Our aquariums are more resilient than that. If we set them up to be. Common sense aquarium management, with an eye towards how natural aquatic systems work, is key, IMHO.

Of course, an aquarium is NOT a stream, river, etc. However, the same processes and "rules" imposed by Nature that govern the function of these wild ecosystems apply to our little glass and acrylic boxes. It's simply a matter of nuance in management and understanding how these wild habitats work on a basic level.

I'd love to keep us in the mindset of thinking about our aquariums as little "microcosms", not just "aquatic dioramas."

Think about this: The idea of a substrate "enriched" with botanical materials is completely in line with the practices of a "dirted" planted aquarium. In our case, not only will there be an abundance of material for microorganisms and crustaceans to forage and multiply among, trace elements and essential plant nutrients will also be present in such a substrate. And, of course there will be the constant addition of tannins and humic substances into the water,  which provide many known benefits for fishes as well.

The best of both worlds, I think.

Again, it's not about creating a cool Instagram-ready "look."

It's about trying to create an entire aquatic ecosystem.

Embracing and fostering not just the look, but the very processes and functions which take place in natural aquatic systems. Is it as simple as crushing some leaves, adding some coconut-based material, covering it up with sand and you have an "instant tropical stream?" No, of course not. There is no such "magic bullet!" You need to look at things sort of "holistically"- with an eye towards nutrient export and long-term maintenance. 

For those of you who are adventurous, experimental, diligent, and otherwise engaged with managing and observing your aquariums, I think this process offers amazing possibilities. Not only will you gain some fascinating insights and the benefits of "on-board" nutrient export/environmental "enrichment"- you will also get the aesthetics of a more natural-looking substrate as well. (Let's face it, no matter how "function first" we feel that we are, everyone likes a nice-looking aquarium, right?)


So, the best way to "enrich" (for want of a better term) your substrate is to add the  botanical materials and sediments before you fill the tank up with water. In the case of leaves, bits of botanicals, etc., you'd want to have boiled/steeped them previously, so that they are rid of any surface contaminants, and to assure that their tissues are saturated enough to get them to sink immediately upon submersion.

There is no set "process" for this, other than to mix these materials into the upper layers of substrate as you add them. You will just sort of know when you've achieved the look and texture that pleases you (that's the "aesthetic" part!), and take comfort in knowing that just about any amount of these materials that you're adding to your system will help accomplish the "functional" aspect.

Once your substrate is in place, Nature takes over and the materials develop that lovely "patina" of fugal growth, biofilms and microbial colonization, and start breaking down. Some may be moved about by the grazing activities of resident fishes, or otherwise slowly redistributed around the aquarium.

A literal "active substrate", indeed! Yet, something that is fascinating and beautiful for those who give the idea a shot!

 At this point, I have to admit that there are many hobbyists who will never find any sort of appeal whatsoever in a botanically-enriched substrate, dark and complex, filled with all sorts of "stuff" besides just sand. The so-called "Nature Aquarium" cult crowd, or the truly "artistic" aquascaping people, for example, will likely never approve of this idea, because it looks "dirty" to them, and because some of the aesthetic and management "work" is being "ceded" to Nature. They need to be in control.

I admit, the simple practice of adding "botanical stuff" into our aquariums is not some "high concept thing." However, the impacts on the water chemistry and overall aquatic environment- not to mention, on our fishes- are profound, fascinating, and real!

Being careful and taking the time to clean, prepare, and add botanicals to your aquarium in a measured manner always yields a better outcome. Going slowly also gives you the opportunity to address any issues that you might have before they become critical, especially when you're experimenting with some of these ideas.

It just makes sense to be patient. The rewards are so great.

From a maintenance standpoint, it's pretty straightforward. You monitor your environmental parameters regularly, and conduct routine water exchanges, taking care not to siphon aggressively from the substrate. You simply don't want to disrupt the very processes within the substrate that you're trying to foster. And trust me, your fishes will spend a lot of time foraging among it.

Much like what occurs spontaneously in Nature, the materials that we deliberately place on the bottom of the aquarium will become an active, integral part of the ecosystem

Like so many things we discuss here, I admit that simply don't have all the answers about every aspect of botanically-supplemented substrates. There is a ton to learn! That's part of the joy of this process- sort of figuring out why and how it works as you're enjoying the success!

Playing with ideas like botanically supplemented substrates truly pushes the boundaries between what we do al the time in the hobby, and those outer regions where few have tread before. There will be challenges, discoveries..and rewards for taking this road less travelled.

And that's part of the fun, isn't it?

Stay creative. Stay brave. Stay curious. Stay diligent...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

April 04, 2022


How it all works.

We get questions. Lots of questions.

Questions about what we call the "botanical method aquarium."

A sort of a funny name for a rather serious approach to aquarium keeping.

What does it mean. How does it all work? And, doesn't the whole idea seem a bit...well- crazy?

It does seem a bit crazy, doesn't it? I mean, we're telling you to do stuff that seems like it's the perfect recipe for a "dirty" tank.  We espouse literally throwing in leaves, twigs, and seed pods in your aquarium, and allowing them to recruit fungal growths, bacterial biofilms, and ultimately to decompose. We value the resulting detritus and the life forms which accompany it. This is absolutely the opposite of pretty much any "methodology" which has been presented to the aquarium hobby for generations.

Yeah, it's definitely one of those things that does seem to be counter-intuitive- at least, based on the current hobby narrative of what is considered "best practices."

In the aquarium hobby, we seem to have this idea that aquariums should be absolutely pristine and not filled with decomposing organic materials. It's a philosophy that's no doubt grounded in trying to help the greatest number of aquarists develop good habits, and is perpetuated on social media, with thousands of these surgically sterile "natural" aquairums thrown into our news feeds daily.

I can't necessarily trash on the idea of preaching good habits. I mean, proper water quality management and routines are important for long term success. A tank full of uneaten fish food and fish waste is a recipe for trouble. However, I think that somewhere along the way, we went a little overboard and started to obsess about cleanliness of our tanks, to the point where almost any algae, detritus, and heaven forbid, biofilms and fungal growth, would be interpreted as a sign of disaster!

So we scrub and scrape, and siphon...

And I think that this "doctrine of radical cleanliness" has actually caused more problems than it has solved. In our pursuit of this radical cleanliness, we've disrupted beneficial biological processes and dramatically slowed down/limited, or even failed to foster significant microbiomes in our aquaria, which I believe has resulted in a lots of tanks with instability and wildly fluctuating environmental parameters. Ironically, these conditions are the very things that drive many hobbyists to keep their tanks obsessively "clean" in the first place! 

As a result, we've developed a "dependency" on high-priced filters, media and additives- a sort of "crutch" to make up for the self-inflicted biological shortcomings of our systems. 

IMHO, we've sort of lost touch with Nature- and the accompanying skill set required to successfully work with natural processes to manage long-term sustainable aquarium systems. We've taken it to a crazy extreme.

Trust Nature a bit more.

I have almost adapted a radically opposing philosophy to this that says "clean"= "unstable!"

Seriously. On a basic biological level, that's what I think the hobby-accepted definition of "clean" means in practice. Unstable, because it essentially "fights" natural processes in order to keep a physically clean environment. It replaces biology with mechanical cleanliness.

The reality is that we can and should find a "middle ground" between complete disregard for basic aquarium husbandry, and a fanatical effort to create "surgical sterility" in our tanks. For some reason, the hobby as a whole has found it tricky to walk this line. I think our approach can fill that void. If anything, the "botanical method" is sort of a call to pull us back towards the side of Nature, relying on not only good old "hobbyist common sense" and effort, but to form an alliance with the many organisms which comprise the microbiome in our aquariums.


And it starts with understanding what some of these organisms are, why they are beneficial, and allowing them to emerge and proliferate in our aquariums. We talk glowingly about "recruiting" biofilms and fungal growths on these decomposing materials to serve as a nutrient processing "system"

The aquarium itself-or, more specifically- the botanical materials which comprise the botanical-style aquarium "infrastructure" acts as a biological "filter system." Or more precisely, a filter "media" upon which these organisms grow.

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 and fungal growths, 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. "Resistance is futile!" We may not see the famous long, stringy "snot" of our nightmares, but the reality is that they're always present in our tanks to a certain extent, 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.n

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!

What's the hardest part about dealing with biofilms? Accepting their "unique" appearance, and wrapping your head around the fact that these life forms are desirable and normal! 

So, when you are starting up a botanical-method aquarium, you'd be well advised to adopt the mindset that you're creating a small closed aquatic ecosystem, with a variety of unique life forms co-existing at a number of levels. And the point of it all is not just to construct an ecology, but to provide a form of supplemental nutrition for the various inhabitants of your aquarium.

One thing that's unique about the botanical method approach is that we tend to accept the idea of decomposing materials accumulating in our systems. We understand that they act, to a certain extent, as "fuel" for the micro and macrofauna which reside in the aquarium, and that they perform this function as long as they are present in the system.

Our aquariums, much like the wild habitats we strive to replicate, are constantly evolving, accumulating new materials, and creating new physical habitats for fishes to forage among. New food sources and chemical/energy inputs are important to the biological diversity and continuity of the flooded forests and streams of the tropics, and they play a similar role in our aquariums.

So, when you set up your new tank, and add a whole bunch of leaves and seed pods, you're essentially mimicking many of the processes which occur in the wild that foster a growing, dynamic, ecology! And that includes the appearance and proliferation of biofilm and "that other stringy-looking stuff"- fungi.

The fungi which we occur in our botanical method aquariums are known as aquatic hyphomycetes produce enzymes which break down botanical materials in water. Essentially, they are primary influencers of leaf maceration. They're remarkably efficient at what they do, too. In as little as 3 weeks, as much as 15% of the decomposing leaf biomass in many wild aquatic habitats is effectively  "processed" by fungi, according to one study I found!

Aquatic hyphomycetes play a key role in the decomposition of plant litter of terrestrial origin- an ecological process in rain forest streams that allows for the transfer of energy and nutrients to higher trophic levels. 

Read that again, and think about it for a second. This is what ecologists call "nutrient cycling", folks!

These fungi colonize leaf litter and twigs and such soon after they're immersed in water. The fungi mineralize organic carbon and nutrients and convert coarse particulate matter into fine particulate organic matter. They also increase leaf litter palatability to "shredders" (fishes and other aquatic organisms which consume leaf litter as part of their diet), which helps facilitate physical fragmentation.

Fungi tend to colonize wood and botanical materials, because they offer them a lot of surface area to thrive and live out their life cycle. And the abundant cellulose, hemicellulose, and lignin- the major components of wood and botanical materials- are degraded by fungi, which posses enzymes that can digest and assimilate these materials and their associated organics!

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?

In aquarium work, we see fungal colonization on wood and leaves all the time. And we collectively shit ourselves when it appears in our tanks. Yet, it's really nothing compared to the abundance of this stuff in Nature. Most hobbyists will look on in complete horror if they saw the same extensive amount of fungal growth on their carefully selected, artistically arranged wood pieces as they would in virtually any aquatic habitat in Nature!

Yet, it's one of the most common, elegant, and beneficial life forms which occurs in natural aquatic habitats!

It's everywhere.

Of course, fungal colonization of wood and botanicals is but one stage of a long process, which occurs in Nature and our aquariums. And, as hobbyists, once we see those first signs of this stuff, the majority of us tend to reach for the algae scraper or brush and try to remove as much of it as possible- immediately! And sure, this might provide some "aesthetic relief" for some period of time- but it comes right back...because these materials will provide a continuous source of food and colonization sites for fungal growths for some time!

Ultimately, in the aquarium, it will typically subside a bit to a more "aesthetically tolerable" level, but it will always be present in an aquarium in which botanical materials are available for it to colonize. 

I know that the idea of "circumventing" this stuff by removing it upon initial appearance is appealing to many, but the reality is that you're actually interrupting an essential, ecologically beneficial natural process. And, as we know, Nature abhors a vacuum, and new growths will simply return to fill the void, thus prolonging the process.


Let it play out. Your tan will be just fine. Trust me on this.

Again, think about the role of aquatic hyphomycetes in Nature.

Fungal colonization facilitates the access to the energy trapped in deciduous leaves and other botanical materials found in tropical streams for a variety of other organisms to utilize. 

As we know by now, fungi play a huge role in the decomposition of leaves, both in the wild and in the aquarium. By utilizing special enzymes, aquatic fungi can degrade most of the molecular components in leaves, such as cellulose,, hemicelluloses, starch, pectin and even lignin.

Fungi, although not the most attractive-looking organisms, are incredibly useful...and they "play well" with a surprisingly large number of aquatic life forms to create substantial "food webs", both in the wild and in our aquariums!

Natural habitats are absolutely filled with this stuff...It's like the whole game here- an explosion of life-giving materials, free for the taking...

It doesn't look like the dude's pristine "Nature Aquarium" on Instagram, so we freak the fuck out about it when it shows up. Contest judges would never accept such "sloppiness", so we must remove it immediately!

Just don't. Please.

Think about it for a bit.

Yeah, it's another "mental shift", I suppose...one which many of you have already made, no doubt. I certainly look forward to seeing many examples of us utilizing "what we've got" to the advantage of our fishes! AGAIN: A truly "Natural" aquarium is not sterile. It encourages the accumulation of organic materials and other nutrients- not in excess, of course.

Fungi are actually an important food item for other life forms in the aquatic environments tha we love so much!  In one study I stumbled across, gut content of over 100 different aquatic insects collected from submerged wood and leaves showed that fungi comprised part of the diet of more than 60% of them, and, in turn, aquatic fungi were found in gut content analysis of many species of fishes!

Now, there is one consideration: Bacteria (ie; biofilms) and fungi that decompose decaying plant material in turn consume dissolved oxygen for respiration during the process.

This is one reason why we have told you for years that adding a huge amount of botanical material at one time to an established, stable aquarium is a recipe for disaster. There is simply not enough fungal growth or bacteria to handle it. They reproduce extremely rapidly, consuming significant oxygen in the process. That is a recipe for the typical "botanical method aquarium disaster" that we see once in a while.

Bad news for the impatient.

Learn to appreciate going slowly and to accept these life forms in your tanks.

Yeah, I admit, decades ago, I freaked out about seeing fungal growths in my tanks, too. I'd get a bit scared, wondering if something was wrong, and why no one else's aquariums ever seemed to look like mine. I used to think something was really wrong!

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 wild leaf litter zones and how productive and unique they were, and how a wide variety of organisms worked together to make up the ecosystem.

I remember telling myself that what I was seeing in my tanks was remarkably similar to what I saw in images and videos of wild aquatic habitats that I wanted to replicate. They seem to look- and even function- so similarly.

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.

Truth be known, I kind of 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.


There's more going on in our tanks than meets the eye- literally!

Support. Co-dependency. Symbiosis. Whatever you want to call it- the presence of fungi and biofilms in aquatic ecosystems is extremely important to other organisms.

You can call it free biological filtration for your aquarium!

GREAT news for the patient, the studious, and the accepting.

We are creating a big, interwoven set of ecological dependencies in our botanical method aquariums. One which benefits life forms on a variety of levels. 

That's just a very basic, generalized overview of "how it all works." 

Stay curious. Stay intrigued. Stay diligent. Stay brave...

And Stay Wet.


Scott Fellman

Tannin Aquatics 



March 29, 2022


A "clean start?"

When you think about it, setting the stage for life in our aquariums is the SINGLE most important thing that we do. If we utilize a different mind set, and deploy a lot more patience for the process, we start to look at it a bit differently.

I mean, sure, you want to rinse sand as clean as possible. You want make sure that you have a piece of wood that's been soaked for a while, and..

Wait, DO you? Why is that?

I mean, sure, if you don't rinse your sand carefully, you'll get some cloudy water-possibly for weeks...no argument there. I mean, it eventually clears, but it can be pretty annoying, huh? Is it "harmful", though? I mean, your likely not adding fishes from day one, so why is it a problem. And what exactly is the "problem" that silty water causes for your fishes? 

And if you don't clean your driftwood carefully, you're liable to have some soil or other "dirt" get into your system, and perhaps more tannins being released into the water column, which leads to...well, what does it lead to? 

I mean, an aquarium is not a "sterile" habitat.

The natural aquatic habits, although comprised of many millions times the volumes of water that we have in our tanks- are typically not "pristine", either- right? I mean, soils from terrestrial geologic activity carry with them decomposing matter, leaves, etc, all of which impact the chemistry, oxygen-carrying capacity, biological activity, and of course, the visual appearance of the water.

And that's kind of what our whole botanical-method aquarium adventure is all about- utilizing the "imperfect" nature of the materials at our disposal, and fostering and appreciating the natural interactions which take place in aquatic habitats. Understanding that descriptors such as "crystal clear" and "pristine" only apply to some aquatic habitats, and that there is real beauty in all types of aquatic habitats.

Indeed, the real "magic", in many instances, occurs in the more murky, turbid, not-so-crystal-clear waters of the world. And if we understand and accept this, we're likely to start our aquariums with a bit less concern over absolute "sterile perfection."

Rather, I feel that we should embrace the mindset that every leaf, every piece of wood, every bit of substrate in our aquariums is actually a sort of "catalyst" for sparking biodiversity and yes- a new view of aesthetics in our aquariums. The basis for the developing ecology within your aquarium.

Now, I'm not saying that we should NOT ever rinse sand, or soak wood before adding it to our tanks. I'm not suggesting that we throw caution to the wind and just toss stuff from any old source into our tanks without inspection or at least a rinse. Heavens, no.

What I AM suggesting is that we don't "lose our shit" if our water gets a little bit turbid or there is a bit of botanical detritus accumulating on the substrate, especially when the tank is brand new. And guess what? We don't have to start a tank with brand new, right-from-the-bag substrate.

Of course not.

We can utilize some old substrate from another established, healthy tank (we have done this as a hobby for generations, for the purpose of "jump starting bacterial growth) for the purpose of providing a different aesthetic as well. It's a time-honored, proven technique.

And, you can/should take it further: Use that slightly algae-covered piece of driftwood or rock in your brand new tank. Add those partial-decomposed leaves or fungal-encrusted oak twigs from that established tank into your new one.This gives a more "broken-in look", and helps foster a habitat more favorable to the growth of the microorganisms, fungi, and other creatures which comprise an important part of our closed aquarium ecosystems.

In fact, in a botanical-style aquarium, facilitating the rapid growth of such biotia is foundational. The whole idea is to allow life to establish itself and proliferate at so many levels- so adding materials to our tanks which facilitate this process- which contain the "ingredients" to jump-start your ecology- just makes a lot of sense, right?

And, hey- It's okay for your tank to look a bit "established" right from the start.

In fact, I think most of us actually would prefer that! It's okay to embrace this idea of not overly preparing and cleaning well-sourced materials and adding them to your aquarium. From a functional AND aesthetic standpoint. Employ good husbandry, careful observation, and common sense when starting and managing your new aquarium.

Don't add those leaves that you collected from the gutter in front of the automobile paint shop, that ditch behind the carwash, or that new construction site...If you're going to "minimally prepare" materials for aquarium use, make sure that they are from sources free of pollution...

And don't fight the appearance of your tank in these early phases. You're building an ecosystem; attempting to follow Nature's cues. Terrestrial materials impart all sorts of organic and inorganic substances to the water. These, in turn, help foster life.

In the flooded forests, ponds, and streams of the world, materials which fall into the water break down, and they alter it biologically, chemically, and even physically. 

It's something that we as aquarists have to accept in our tanks, which is not always easy for us, right?Decomposition, detritus, biofilms- all that stuff looks, well- different than what we've been told over the years is "proper" for an aquarium. And, it's as much a perception issue as it is a husbandry one.  I mean, we're talking about materials from decomposing botanicals and wood, as opposed to uneaten food, fish waste, and such.

What's really cool about this is that, in our community, we aren't seeing hobbyists freak out over some of the aesthetics previously associated with "dirty!" 

It's fundamental.

And it's not like we've told ourselves that it's acceptable to not change water, siphon detritus, overstock, or overfeed. Nope. We can still perform excellent regular husbandry routines on botanical-style aquariums. We still monitor water chemistry. We're still diligent aquarists. And we still might have so-called "dirty" looking water!

And, that's kind of what Nature wants, right?

The important thing for us to do as hobbyists is to understand that, just because the tank looks like it might fit our definition of "dirty"- it often times isn't. It's a mental shift...again.

The desire to have a "super-clean" (whatever THAT actually means...) tank is, I think, rooted primarily in aesthetics, and is a decidedly impractical goal for many hobbyists. When we strive to create a spotless tank, we're essentially fighting against what Nature does...and what the natural aquatic ecosystem requires. 

When you're siphoning out every speck of detritus, or scrubbing away all of the fungal growth on your leaves, you're essentially decimating a significant population of the life forms which make up the aquariums ecosystem, as well as their food sources. It's literally as simple as that.

If we make the assumption that, just because something looks contrary to what our hobby aesthetic "norms" say is "attractive" or "safe" or whatever, we miss out on the opportunity to create an ecologically functional aquarium, replete with a diversity of life forms.

So, in summary- keep your aquarium "clean"- meaning, keep the water quality high, and the environmental conditions stable. However, don't obsess over "sterility." Look to the overall health of your animals and their aquarium as your cue.

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

And Stay Wet.


Scott Fellman

Tannin Aquatics 


March 20, 2022


Why do we put up with... glassware?

Someone asked me the other day to write more posts to share my feelings about stuff that "bothers me about the hobby." Literally, asking me to bitch and moan and rant about something I dislike.

Yeah, after thinking on it a bit, I realized that this was a sort of "trap"- because asking me to complain about anything is almost guaranteed to piss someone off. As you know, I rarely hold back. I realized that there are some things in the hobby which leave me both flummoxed and laughing at the same time. 

One of these topics is why we as hobbyists tend to favor certain things which are simply atrocious. (okay, "atrocious" IMHO, anyways...I mean- you asked, right?)

I think we put up with a lot of bad stuff and practices just because it’s so popular or pervasive in the hobby. I'm not sure why this is, but it's something I think about a lot. The idea of using gear, following techniques, and working with certain fishes or plants- even though, deep down inside, I am willing to be that we're not really big fans of them- is just sort of...strange.

Someone asked me what I though the worst piece of gear is in the freshwater hobby! Well, there are likely a few...

However, let's focus on one item that you know that I personally despise: So-called "glassware" (you know, "Lily Pipes" and all that stuff) that is pervasive in the freshwater hobby. Basically, filter intakes and returns made of glass, used in aquariums. When they first emerged on the scene, they were a real step up from the green and brown translucent plastic ones that came with canister filters. They do have a certain aesthetic to them, I"ll freely admit.

Yet, the only thing they offer over the plastics is a different look.


And, like so many things in the hobby, when aesthetics win out over almost everything else, there are usually compromises. And when it comes to glassware, there are a bunch of compromises.

First off, sizing the damn things to get he correct one for your tank is a freaking mystery. You have to make sure that it fits the diameter of the hose you're using from your canister filter...Then, you need to figure out if the one you want will fit into your tank. This reminds me of a other thing I hate- deciding which of the many different sized packages of paper towels or toilet paper to purchase at the local Target to get the maximum value . ("So, this package says 8 rolls =12 full size roles , and has 300 ft of paper..."WTF?). 

LIke, why can't manufacturers simply say that this will fit the hose on your Eheim 2215, or whatever, and can fit into a tank with a depth of "X" inches/cm? Just make it less of a chore to simply purchase the awful thing. It's like you have to have "tribal knowledge " just to pay "bend-over" prices for the correct model of one of these stupid devices for your aquarium!

And, these so called "Lily Pipes" and intakes are rather fragile, tending to break during basic tasks, like simply removing them for cleaning and maintenance if you don't employ near surgical skills to remove them from the hose. And, being clear, they easily RECRUIT algae and organic discoloration, so the much-desired "aesthetics" are easily compromised by them simply being present in your tank, doing what they're intended to do. 

Now, sure, the advice is to carefully clean them as part of your regular maintenance. If you don't, you'll end up with a brown or green "Lily Pipe", which I suppose defeats the purpose of the thing, right?  I'll ask this only once, and I know it will result in a flurry of hate- but this is my opinion: Why in the hell do you add a product with only the most basic utilitarian function (I mean, it's a FILTER RETURN!) that is a) really expensive, and b) requires extra-careful handling and an extra level of dedicated maintenance?

Is the "aesthetic benefit" of glassware so important as to be worth all of this extra hassle, attention and care? It obviously is, to a lot of hobbyists who may or may not be brainwashed about them. (Great- I violated the first rule of good writing..."Never insult your audience" Well, f--- That. lol)

Personally, I'd rather spend time, money, and effort on stuff which actually matters, like- I dunno- the fishes, the hardscape materials, lighting, return pumps, or the aquarium itself, instead of a fragile piece of "art" with no discernible benefits over "conventional" plastic intake/output pipes, save aesthetics and "cachet." Now, there are also stainless versions of some of this hardware, and if you're just super obsessed with how your freakin' filter return looks, those at least don't discolor as readily as glass, and won't snap the minute you look at them wrong, huh?

Which begs the question: Why there aren't  there alternatives? Like 3-D-printed versions of "Lily Pipes" and intakes, or even more durable ceramic, better-colored plastics, etc., is something I can't fully grasp. Are they that much pricier than glass? Sounds like a great market niche for some budding entrepreneur with the right skill set!

Meanwhile, year after year, people plunk down hard-earned cash (ranging from $40.00 to $90 or more!) on something which has a role that can easily be performed by a a $5.00 part (and has for decades). It's just bizarre. Often, these purchases are justified by praising their aesthetics and the "social media cachet" of using them. Meanwhile, many of these same hobbyists who worship in the "Temple of The Holy Glassware" will use shitty, underpowered, feature-impoverished LED lighting systems on their "high tech" planted tanks, just to save a few bucks, while employing $200 worth of return pipes from their filter! 

Yeah, it's a real head-scratcher. 

And what's the culprit? 

Perhaps it's because we see glassware in tanks everywhere. It's perverse in social media and elsewhere. Almost every highly-regarded 'scaper uses them in all of their tanks. Amano used them. The message is that It's what you're supposed to use. Now, look- I'm not blindly blaming social media or the late Mr. Amano- it's just the way stuff is shared nowadays leaves little in the way of alternatives in the minds of many. It's the underlying psychology that's the real culprit, IMHO.  

People want to belong.  And a piece of blown glass apparently satisfies this need. Yeah, now I'm speaking amateur psycho-babble to hate on glassware. What a dick I am...😳

Well, I actually do think it's a sort of "peer pressure" sort of thing; a desire to be in the "cool club." Use of "glassware" represents an adherence to a hobby movement, and is a statement that you (the hobbyist) are doing something that is inline with expectations of the movement. I've actually seen a few forum posts where people asked for a critique of their aquascape, and the main suggestion was to ditch the "ugly" filter intakes and outlets  in place of...glass pipes! 

That's what my British friends call a "face palm moment!" Like, really?

Now, hell- on some levels, I do get it. I mean, you have something that's "function first"- a necessary evil, if you will- so why not make an aesthetic improvement upon it to minimize the "ugliness?" I can't argue with that. I mean, enjoy the hobby the way you want, right? 

It's the inconsistency of the embrace of "aesthetics first" which baffles me.

I mean, you're totally okay with the return lines for the filter running out of the stand on the sides of the tank, in full view, right? That's somehow not an issue for you, but green plastic returns are? Now, I find it hard to believe that some manufacturer somewhere hasn't come out with a better-looking, yet still functional alternative? Manufacturers have figured out how to get heaters and UV into the canister filters themselves- you think that they can't come up with a better return or intake?

Are there alternatives to glassware that offer more function? I think so...Of course, big moves can share up the entire industry. Yet, what about "all in one" tanks, or tanks with better looking integrated external overflows and returns?  THAT would be the ultimate aesthetic game changer- no visible intakes and returns?

There must be someone out there with design/fabrication "chops" who can tackle this; or who thinks it's worth doing?

Show yourself, soon!

And the "glassware" still reigns supreme as the ultimate statement in sexy design for many...

Scarier yet, to me, is that I've noticed several newly-minted "crossover" freshwater "high-tech planted" aquarists wanting to build "reef tanks" and trying to figure out how they can adapt glassware to reef tank use. They're discussing these on "build thread" forums, sharing all sorts of machinations they're going through trying to adapt these shitty devices to their ideas for a "reef" tank. I mean, on the reef side, we do enough lame things without taking on more lousy hardware...Thankfully, many of the reef guys responding to these threads are gently and politely pushing back on the use of this inefficient crap for reefs.

Bless them.

Ouch! I'm being a real A-hole about this. Just bitching away about something that is not a real "problem" for the hobby...

But you asked. And I can go on and on. So, yeah, I'm being a total ass.

Yeah, I freely admit it.

However, IMHO, a stupid idea is still a stupid idea, regardless of which side of the "salinity line" you work in. And I think that glassware is stupid. And what's worse is that I don't have a really great alternative- I admit. Other than to simply boycott stupid glassware and encourage others to do the same, lol. 

I guess I'm heaping on the hate on glassware because it represents ( in my twisted mind) some form of willing conformity and allegiance to something which provides only a superficial "advantage" over what's already out there. That, to me- the  "conformity" part- is a big problem to me. It stifles originality and progress; creates dogma.

"Wow, Fellman, it's just a fucking piece of glass! You're way overboard on this!"

Well, sure, on a pragmatic level, it is just a piece of glass But it's also a sort of "Metaphorical shackle" in my estimation. The blind reverence and lack of demand for something better from the industry forces a weird sort of conformity, in my mind at least. We kind of get what we deserve, right?

I probably simply "don't get it." Maybe it's 'cause I'm just bitter, having broken a lot of these over the years (a couple actually intentionally, I admit!) and simply hating them. However, I do like the sort of "mental exercise" I can get by looking long and hard (and in an admittedly biased fashion, no doubt) at something which I find somehow problematic in the hobby, contemplating why it exists, and at least thinking a bit on possible alternatives, practical or otherwise.

Sure, we could likely do without my vitriol when contemplating such ideas, but it never hurts to be a bit critical; to question why stuff is the way it is.

So, yeah, in the end, this "first world problem" (in my head, at least) of "glassware" is likely a bit silly, but it does show a little light on the "how's and why's" of the aquarium hobby.

My advice too you: Don't be afraid to question, consider alternatives, and create demand fo them if they don't exist- and to not simply accept everything that is taken as "the way" in the hobby.

Stay bold. Stay creative. Stay defiant. Stay observant. Stay engaged...

And Stay Wet.


Scott Fellman

Tannin Aquatics 








March 15, 2022

1 comment

Bending the rules?

For some reason, the aquarium hobby loves to impose "rules" on everything. Particularly about what you "can" and "cannot" do in your tanks. Now, look, I"m the first guy to tell you that some "rules" are important...

Like, Nature's rules about what can and cannot work. You know, the nitrogen cycle, stuff like that. "Universal Aquarium Constants" that, although we'd love to skirt them, cheat a bit, and work around them- we simply can't...because the Universe doesn't work that way.

Don't overstock your tank. Don't add a ton of fishes to a new tank all at once. Don't mix wildly incompatible fishes in the same tank. Don't neglect the basic tenants of aquarium husbandry. 

"Rules" that are supported by common sense, and when broken, will almost always manifest in ways that can be harmful- even devastating - for your fishes. 

Yet, in the hobby, we seem to love to fall back on "rules" or "doctrines" in order to justify things that we believe in- or which conveniently fit the narrative we're trying to push. We are admonished by experts and the community at large not to do stuff a certain way, lest some bad outcome ensue. Often, the reasons given are either ludicrous ("because that's not the way you're supposed to do it.."), misguided, based on outdated information- or worse yet, regurgitated third-hand information. 

Often, this stuff is metered out with air of undisputed authority by those who fancy themselves "thought leaders" or self anointed "experts" who may have never even attempted anything remotely close to what is being discussed.

This is not helpful.

I recall facing this kind of "pushback" when I first started Tannin Aquatics in 2015, pushing our emerging philosophy of truly natural, botanical method aquariums.

We took "incoming fire" from a lot of directions.

Like so many things in the hobby, this "advice" and the "cautions" were often dished out by well-meaning hobbyists who, with no firsthand experience, were simply "regurgitating" stuff they've heard for years and years from others. The result was that these those types of aquariums became a sort of hobby "pariah", relegated to receiving hushed whispers in discussions. Hobbyists who dared pierce the "botanical barrier" were often looked at as foolhardy, perhaps even rebellious souls who simply wanted to do something that made others wince.

And some of these people were real assholes about it, for reasons which I still cannot figure out why.

I'm not exaggerating here.

This was literally what botanical method aquarium keeping was like for many years. And I found it a bit funny, because the practices that we developed and embraced were ecologically sound, and at least as methodical and well-thought-out as those being used to create "blackwater aquariums" for decades before we arrived on the scene.

I mean, "aquarium blackwater" conditions were embraced by some hobbyists who bred various species of fishes, like killifishes, characins, Apistos, and the like for generations...

But, curiously- only when they were trying to breed these fishes.

And that was somehow "acceptable" to the self-appointed hobby "guardians"- yet maintaining these ecological conditions 365 days a year was somehow foolhardy and rebellious?

And I found that part interesting...Like, why would hobbyists only utilize these conditions when they were trying to breed these fishes? What about the other 360 days of the year, right? I mean, the benefits were at least rudimentarily understood...So why not just keep the fishes under these environmental conditions- the ones they evolved under for eons- full time? 

Like, wouldn't that make sense? Why was this problematic?

I just couldn't get my head around that.

So I joined a small, rather quiet, yet adventurous group of hobbyists who decided that there was "something to this stuff..." and did just that. My world was filled with reef tanks and blackwater aquariums filled with decomposing leaves and seed pods.It was fun. Enlightening. And I learned a ton.

Oh, and I never had a goddam "pH crash", either.

Notice I never once have said that I "invented this stuff.."- 'cause I didn't. No one did. No one "created" this idea or "invented" the processes...No one created rules for how this stuff works.

Nature did.



Now look, it's perfectly logical to want to create "best practices", etc. in the hobby. We want to have our fellow hobbyists succeed. That's how the hobby thrives. A lot of them make sense. They help other hobbyists recreate the same successes.

But all of those so-called "rules" and "you can't" proclamations from "experts" don't always achieve that. Sure, they might discourage a few downright incompetent hobbyists from going down a path to near-certain failure (one that they were likely headed down regardless of what they did, btw), but for the bulk of hobbyists, I think that they stifle both creativity and progress. They simply discourage people from trying new ideas and approaches to stuff.

We don't want to do that as a hobby. We'll stagnate.

Listen to the advice of good-hearted fellow hobbyists. However, balance it with study and observation.

I'm a firm believer in looking to Nature for inspiration in both form and function.  There is so much we can learn by observing the wild aquatic habitats of the world and considering how they function. You only have to read this blog, listen to my podcast, or attend my lectures to get your head around that.

Now, being a progressive hobbyist and a student of Nature doesn't absolve you from common sense. And look, just because we tell you something is cool and successful doesn't mean that it's the best way to go.

And when I see this  going the other direction, I'm gonna call it out, too. 

Look, every single aquarium doesn't have to have decomposing leaves, biofilms, brown water, and sediment-filled substrate to be called "inspired by Nature" or whatever.  Last I read, the processes which govern the nitrogen cycle of my aquariums in Los Angeles are the same ones that govern the nitrogen cycle in the igarapes of Amazonia... So, yeah.

And every aquarium doesn't have to be a copy of a specific natural habitat or biotope. Otherwise, every tank becomes some tightly-labeled, rule-imposed enclosure, and we end up in the same old militant "us vs. them"position that has turned off hobbyists to some of these "movements" for years.


I've seen this sort of crap turning up on biotope enthusiast forums and blackwater aquarium groups lately. Ridiculous nitpicking that serves no purpose except to expose those who "call out" others' efforts as jerks, quite honestly. There are some incredibly talented, really great hobbyists in that arena- and there is much to learn from them. Yeah, there are also some total jerks who feel that every tank needs to meet their extremely rigid "standards" to be considered some sort of "serious" work.

It's crazy.

Do what YOU love- in a way that YOU love to do it.

Call it what you want, but be mindful of the words you use and what they mean. If you must apply a "label" to your work, I think "biotope-inspired" or "natural style" are great, much more apt, broad descriptors for hobbyists to use. I think they'd cause far fewer skirmishes, lol. When we get right down to it, even the mosthardcore "biotope aquarium" as lauded by "the establishment" in that world still isn't 100% perfectly accurate. No matter what "they" (whoever the fuck "they" are..) say!

A working definition of the word "biotope" from Wikipedia- a good one, IMHO, is useful:

A biotope is an area of uniform environmental conditions providing a living place for a specific assemblage of plants and animals. Biotope is almost synonymous with the term habitat, which is more commonly used in English-speaking countries. ... The word biotope, literally translated, means an "area where life lives".

And, kind of broad, right? 😆

We should celebrate the art, the research, the effort, and the knowledge that was accumulated (and shared!) in order to create all of these aquariums. Sure, in a competitive situation, it's important to follow the rules of the judging criteria, but for hobby efforts, using a Guava leaf instead of a Bertholletia excelsa leaf (because you can't collect or obtain them legally) is not a disqualifier.

Sorry, guys.

Yeah, if a hobbyists cannot obtain the actual Amazonian leaves (because, I dunno- they're from a protected habitat...), does that invalidate the aquarium from consideration as a "biotope aquarium?"

I mean, c'mon!

I've said it before and I"ll say it again: I'll bet 90% of the most hardcore "judges/critics" of these contests couldn't even tell the difference, once these leaves are submerged, softened, and covered in a patina of biocover.

So why get so dogmatic about these things?

We get really worked up; really pissy about this shit.

Even with the contest winners, you can take this attitude and nitpick to the "nth degree" if you want to use these "standards" (Okay, I will😆):

I mean, what about the substrate? Is it absolutely Rio Negro region "podzol" from the Andes?  No? Oh- NOT A BIOTOPE AQUARIUM!  Is every species of wood used in the tank form the surrounding varzea forest? No?  Oops- NOT A BIOTOPE AQUARIUM! Is every freaking bacteria, fungi, Paramecium, etc. the exact species that comes from the region being represented?

Huh? Is it? 

I think I made my point here. And I will never be loved by the people who organize these contests, and I really could care less. But I will happily point out the inconsistencies as warranted, lol.

You can create unusual, progressive aquariums without falling into the "dogma trap" set by some egotist. You can simply replicate the practices employed by someone else who's willing to share how they do it.

Case in point:

I have been playing a lot over the years with my interpretation of a more "evolved" brackish water aquairum; one which embraces muddy or sedimented substrate, growth of live mangroves, and encourages the accumulation of fallen leaves. It has worked fabulously for many fishes.


Over the years, I've refined the approach so that it is literally a matter of setting up a tank in a certain way, following some simple practices, and you you can easily create an easy-to-manage, ecologically sustainable brackish-water aquarium. No "rules." No "You MUST do this.." admonitions. Just suggested practices to achieve a desired result. 


And the result is that I'm able to easily recreate this enjoyable, successful, easy-to-manage aquarium repeatedly. And so can most any hobbyist who understands the approach, follows our suggestions, and adheres to NATURE'S rules of ecology.

Not my rules. 

Sure, there are other ways to create a successful brackish water aquairum. This is just one approach. One which works repeatedly for me and other hobbyists, so perhaps it's worth checking out. 

Or not. 

It's your call. 

I am not here to nitpick what you do, nor tell you that if you don't follow what works for me that you're some kind of idiot. I will tell you that you should at least consider some of what we talk about here and incorporate it into your tank, because it works repeatedly and can make your life easier.


So, the next time you or someone you know is being called out because you don't conform to their expectations of what they think is "correct" or "proper" or whatever, maybe you could push back just a bit and show them the absurdity of it all... And thank them for giving a damn...And just perhaps, taking the time to say, "Hey- isn't this cool? We all care so much about this stuff that we have an intense passion for it! Wow!"

Imagine how much that would do to bring it back around to what the hobby is all about: Having fun, educating, and sharing.

A world in which any deviation from these standards is seen as "reckless", "sloppy", "undisciplined", or just plain "shitty" ( actual words from hobbyists we've heard over the years...) Comparisons are made of many of these aquairums to Nature, yet, other than the fact that they contain live organisms, most of the tanks that are celebrated by a whole lot of hobbyists fall way short of "Nature", even by their own critical standards!

It's kind of funny to me.

What about celebrating function? What about celebrating sustainability, function over the long term? Those are important things, yet in our "visual-centric" hobby, these are seldom touched on as often as just the superficial appearance of stuff. I mean, we should- but that's only part of the equation.

What caused this mindset to saturate everything?

In my opinion, the misappropriation of the word "Nature" within the hobby has led us to this point. Specific aesthetics of Nature are met with high praise. The stuff which goes agains the "rules" is dismissed out of hand, categorized as "dangerous", undisciplined, etc.

And personally, I feel that's why large parts (not ALL, of course) of the freshwater aquarium hobby have been in a sort of "stagnation" for a couple of decades, a position that definitely opens up me and some of my colleagues to a lot of criticisms. However, they're totally worth enduring, because they leave no doubt about where we stand. And quite frankly, I think I'm correct in this thinking. 

Many hobbyists simply don't want to let go of "traditional" ways of thinking about and approaching aquarium work. Now, sure, you have unbreakable natural rules, like those which govern processes like the nitrogen cycle. You can't get around those. However, the way we interpret and approach many of the things which happen in our aquariums is all up for review, IMHO. And a lot of hobbyists are ready to do this.


At the risk of being a bit weird for quoting myself, I think I expressed a good part of our philosophy here at Tannin in this passage from a piece I wrote a couple of years back:

"Suffice it to say, there are NO rules in rediscovering the unfiltered art beneath the surface. Our "movement" believes in representing Nature as it exists in both form and function, without removing the very attributes of randomness and resulting function that make it so amazing"

We are utterly inspired by this.

This keeps us motivated to push out further. To think about how to try unique and different things.

And occasionally, to bend the rules.

Stay bold. Stay curious. Stay steady. Stay motivated...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


March 02, 2022


What causes that "haze" in botanical-method aquariums?

We talk an awful lot about the color of the water in our botanical-method aquariums, don't we? It makes sense, because the color is truly one of the big "aesthetic attractions" of these types of systems. 

However, there is another issue which is quite common in botanical-method aquariums- a sort of "haziness" to the water. Particularly in the earliest phases,  botanical-laden aquariums seem to have a "haze" that is slow to clear.

What causes this?

Now, part of this haze is no doubt due to the breakdown of the leaves, pods, etc. that we use. Surface dirt, lignin, sugars, and other compounds, bound up in the tissues and multi-faceted structure of the botanicals, is released into the water upon the initial submergence of these materials. And, the fact that many of us tend to not use a lot of chemical filtration media in our tanks might have some impact on that, as well.

As these materials begin to decompose, they release many of their constituent chemical components into the water, which of course, has a visual component that we all see. 

So, is this a problem for our "aquariums?"

Well, it usually isn't a problem in my experience, but I suppose that it could could be. I mean, if you have a significant quantity of organic materials- bioload- accumulating in your tank, water quality could be degraded. Concerned about what the "haze" or cloudiness means for the water quality of your tank? Conduct some water quality tests. 

Another reason for this haziness could be a burst of microorganism/bacterial growth, which impacts the visual clarity as populations multiply rapidly in the "fertile" environment of a botanical system, with its wealth of organic materials supplied by the decomposing matter upon which these life forms feed.

Now, I have placed a few drops of tank water under a microscope early in the life of several botanical-style tanks, and I did see quite a bit of microorganisms swimming around in there. Of course, I am not a microbiologist, and for me to make any conclusive statements about "density" or "diversity" of the life forms I saw swimming around in my samples is a bit too amateurish! That being said, in most of these samples, I saw a lot of "some sort" of life forms swimming around in the water! 

Generally, I've found that the sort of "cloudiness" will typically clear after a week or two, as the "tug of war" between bacteria and "infusoria" achieves a sort of "equilibrium."

At this point, I should mention that you could intervene in this if you wanted to...Performing larger water exchanges, employing chemical/very fine mechanical filtration media, etc. Personally, I have learned over the years NOT to let this stuff phase me. I suppose I'm so deep in my own "mindset" about letting nature do its thing, that I don't do much to combat it...

Once this initial "microbial haze phase" passes, there are other aspects to the water clarity which will continue to emerge. And I think that these aspects are similar to what we observe in nature.

For example, I've noticed that in many of my aquariums, particularly those with certain types of wood (like mangrove, newer Mopani, etc.), you'll get more of this "patina" to the water. Again, I'm in the realm of speculation here, but I can't help but wonder if certain wood and botanical materials/leaves have a greater content of organic materials (or more readily release these materials into the water because of their structure), lignin, tannins, etc.

One of my friends calls this "flavor", and his moniker makes sense, when you think about it!

And I think that this is a really interesting phenomenon, which is distinctive to our botanical-stye blackwater/brackish aquariums. To accept it is a choice, and it definitely requires the adoption of a mindset shift to appreciate that this is very similar to what we see in many of the natural aquatic systems that we attempt to replicate.

Of course,  an aquarium is NOT an open, natural system, and that there are fundamental differences between the two. However, to see some of the processes, aesthetics, and what we call "functional analogies" (i.e.; the way materials break down, re-distribute within the tank, and how the aesthetics and water chemistry are affected by water exchanges, etc.) take place in our aquariums, we can't help but think that we're "on to something" here.


Actually, we've talked about it a lot here, but I think it's something that's going to always come up in our little hobby speciality. 

At this point, even though it sounds a bit redundant- let's sort of summarize what contributes to this stuff...

The reality is that, IMHO, many of the causes are biological in nature. In the case of our botanical-method aquariums, the cloudiness could also be caused, at least in part- by the dissolving of the botanicals themselves. Most plant parts, such as seed pods and such, are comprised of materials such as lignin, cellulose, etc., and their constituent sugars, starches, etc. And, because of this composition, will release these materials into the water column as they break down.

Now, this haziness, in general, may be a "tip off" to some other issues in the aquarium. And, as we all know, it can usually be caused by a few factors:

1) Improperly cleaned substrate or decorative materials, such as driftwood, etc. (creating a "haze" of micro-sized dust particles, which float in the water column).

2) Bacterial blooms (typically caused by a heavy bioload in a system not capable of handling it. Ie; a new tank with a filter that is not fully established and a full compliment of livestock).

3) Algae blooms which can both cloud AND color the water (usually caused by excessive nutrients and too much light for a given system).

4) Poor husbandry, which results in heavy decomposition, and more bacterial blooms and biological waste affecting water clarity. This is, of course, a rather urgent matter to be attended to, as there are possible serious consequences to the life in your system.

And, curiously enough, the "remedy" for hazy or cloudy water in virtually every situation is similar: Water exchanges, use of chemical filtration media (activated carbon, etc.), reduced light (in the case of algal blooms), improved husbandry techniques (i.e.; better feeding practices and more frequent maintenance), and, perhaps most important- the passage of time.

Of course, with the haziness or "cloudiness" caused by our "technique" or application of botanicals is a slightly different story. These are sort of "natural consequences" of what we do..

In Nature, we see these types of water characteristics in a variety of habitats. While they may not conform to everyone's idea of "beauty", there really IS an elegance, a compelling vibe, and a function to this. 

Fish don't care that their water is tinted, a bit turbid, and sometimes downright cloudy, as long as the other environmental characteristics of the water are satisfactory.

As we've discussed a lot lately, we're absolutely obsessed with the natural processes and aesthetics of decomposing materials and sediments in our aquariums. And of course, this comes with the requirement of us to accept some "unique" aesthetic characteristics, of course!

It's almost like our idealized aesthetic perceptions of what we feel water should look like in an aquarium have conditioned us as a hobby to sort of gently disregard what it truly looks like in the habitats from which our fishes evolved.

So, regardless of what causes the "haze" in your aquarium, keep a clear focus on what's really important- the health of your fishes, above everything.

Stay dedicated. Stay thoughtful. Stay observant. Stay patient...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


February 25, 2022


"Permission" to evolve?

I don't know about you, but I've had this unwritten rule about keeping an aquarium for an indefinite period of time without breaking it down. Like, "You have to keep a tank going as long as possible..." Like, if I broke down a tank after less than a couple of years, it was considered a shameful act of failure!

I've always worn this "stick to it" attitude as a sort of "badge of honor"- you know, this idea that I'm some how cool because I resist the temptation to break down my tanks after a few months or whatever.  I would laugh at those famous aquascaping people that seemed to tear down their tanks after just a few months.

"I was Above the fray", right?

What a dummy I was!

And of course, after starting Tannin Aquatics in 2015, I realized that, in order to "spread the gospel" about this emerging botanical method thing, I needed to show a lot of tanks. And of course, that means one of three things: Either I needed to set up a lot of new aquariums myself, recruit a lot of fellow hobbyists to create and share botanical method aquariums, or...I could "iterate" my existing tanks more frequently.


Now, of course, all three are pretty good ways to help accomplish this.  Fortunately, a lot of excited and dedicated fellow hobbyists- you guys- have shared their work on these very pages over the years. Yet, the third idea- frequently changing up my existing tanks- ends up being a very practical (and let's face it, fun) way to show a lot of new looks and share some ideas. 

And the cool thing is that there are actually a number of really cool ways to "evolve" existing tanks and to keep the "ecology" intact while changing up the "look and feel."

And, think about it: This isn't all that different than what happens when a stream overflows and forms a new small tributary. Some of the materials from the established aquatic ecosystem flow into the newly-inundated area, bringing with them their "on-board" population of microorganisms, fungi, and insects.

Nothing's ever wasted, right?

This isn't exactly earth-shattering, I know, but it's worth thinking about vis-a vis our aquarium work. 

And, as we've discussed many times, the same sort of concept applies when you're "remodeling" an existing aquarium; perhaps switching up from say, a "South American theme" to an "African theme", or whatever.

So yeah, I'll literally transfer a fair percentage of the "software" from an existing tank into the new one. The rationale is exactly the same as the rationale for using sand from an established tank which has been practiced for generations in the hobby. And, as you probably recall, 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! 

And the idea of adding "pre-colonized" materials from existing tanks to help "jump start" a new tank is simply a logical and economical practice. Having a big chunk of completely-established ecology transferred from one tank to another is almost too easy a process not to take advantage of!

This is similar to the Japanese aquascaping practice of "sozo haishoku" espoused by the "Master" of this in aquariums, the late Takashi Amano. This is the processs of removing of as much old substrate material as possible along with the plants it contains in an aquarium, and replacing them with new materials.

It preserves the overall "composition" of the layout, but the "softscape" (botanicals and leaves, in our case) could change dramatically. In our botanical method aquariums, it's a little different, but the idea behind it is essentially the same.


Yeah, in the world of the botanical-method aquarium, the idea of leaving the substrate and leaf litter/botanical "bed" intact as you "remodel" isn't exactly a crazy one. It's about preserving ecology over time, and despite changes.

And conceptually, once again, it sort of replicates what occurs in Nature, doesn't it?

Yeah, think about this for just a second.

As we almost constantly discuss, habitats like flooded forests, meadows, vernal pools, igarape, and swollen streams tend to encompass terrestrial habitats, or go through phases where they are terrestrial habitats for a good part of the year.

In these wild habitats, the leaves, branches, soils, and other botanical materials remain in place, or are added to by dynamic, seasonal processes. For the most part, the soil, branches, and a fair amount of the more "durable" seed pods and such remain present during both phases. 

Materials are utilized in the habitat continuously.

As the waters return, the formerly terrestrial physical environment is now transformed into an earthy, twisted, incredibly rich aquatic habitat, which fishes have evolved over eons to live in and utilize for food, protection, and complex, protected spawning areas. 

All of the botanical material-shrubs, grasses, fallen leaves, branches, seed pods, and such, is suddenly submerged; often, currents re-distribute the leaves and seed pods and branches into little pockets and "stands", affecting the (now underwater) "topography" of the landscape.

It's all an elaborate dance, choreographed by Nature, encompassing numerous organisms, each filling a specialized role in the aquatic environment.

So yeah, you can embrace this natural process and attempt to embrace it by evolving your tanks by leaving some of the stuff intact.

Now, this doesn't mean that I guarantee a perfect, "cycle-free" process for you.  I'd be a complete asshole if I asserted that! Every system is different. There are numerous factors which impact the unique functions of a specific tank.

And you can't simply expect instant results, right?

Transferring a good compliment of material to an otherwise brand-new tank isn't going to fool Nature.

On the other hand, in an existing tank, by leaving the bulk of the substrate material and botanicals intact, and continuing to provide "fuel" for the extant biotia by leaving in and adding to the botanicals present in the aquarium, this lack of a "new" cycle makes a lot of sense.


Botanical-method systems are, in my opinion, more robust than they are vulnerable.

I believe that our botanical-method systems, with their diverse and dynamic biology, rebound quickly from disruptions and changes. And I also believe that, because of our approach and it's reliance on biological processes, they establish themselves to a more "stable" state far more quickly than "typical" aquariums do.

Much like the natural systems they purport to represent!

And I also took advantage of the way botanical method aquariums lend themselves so well to this process- evolving them from one "version" to another with relative ease.

It's not a bad idea to evolve existing tanks.

That being said, the biggest hurdle to me has always been the psychological one. The "shame" that I assigned in my own mind if I simply broke down tanks and "recycled" them time and time again. That being said, I slowly (yeah, emphasis on slowly) came around to the idea that this is an effective way to demonstrate new ideas to our growing community.

And I believed then- and still do now- that the value of sharing new ideas, techniques, and information is far more important than any insecurities that I felt about succumbing to what seems like "impatience."

I've finally gotten myself to a more comfortable place after decades...



It's about technique, and evolving it.

And, by preserving the substrate and "refreshing" it a bit with some new materials (ie; sand, sediment, gravel, leaves, and botanicals), you're essentially mimicking some aspects of the way Nature functions in many wild habitats. And, from an aquarium "management" perspective, consider the substrate layer a living organism (or "collective" of living organisms, as it were), and you're sure to look at things a bit differently next time you "re-do" a tank!

Of course, perpetuating the substrate is almost like persuing "eternal youth"- it's not entirely possible to achieve, but you can embrace the idea of renewal and continuity within your aquarium.

The "mental stretches" that we talk about incessantly here are still occurring for me, years into this game. With each pic I see of the natural habitats we want to emulate, and every beautiful aquarium that I see come to life from our community, it's inspiring, interesting, and engaging. I'm seeing and experiencing new things, coming up with new ideas, and trying to understand and embrace the processes and aesthetics in a whole new light.

I am happy to see many of you doing the same. Evolving.

What do you have up next?

Stay motivated. Stay excited. Stay curious. Stay creative...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


February 23, 2022


The color of water...

One of the most common misconceptions about botanical-method aquariums is that they must absolutely be filled with deeply tinted water and replete with fungal-and-biofilm-encrusted decomposing leaves, twigs and seed pods.

Remember, this is a methodology, not a "style of aquascaping", and the reality is that you can have an aquarium which fully embraces the ecological aspects of natural aquatic systems and have clear, slightly tinted, or even turbid water. It's not a "prerequisite" to have that dark brown water. Quite honestly, we see the tinted water as a "collateral" aesthetic benefit of embracing this approach- not the main reason to do it. 

The hobby has somehow latched on to the most superficial aspect of blackwater- the look- and in the social media landscape, the appearance of blackwater has led to a tremendous confusion about what it actually is.

As we've mentioned hundreds of times here, the aquairum definition of "blackwater" seems to apply to any tank which has less than crystal-clear, blue-white water. Remember, in Nature, the term "blackwater" applies to water with a very specific set of chemical characteristics; the color of the water is a result of the presence of various compounds in the water. The visuals may play a huge role in our "interpretation" of what we think "blackwater" is- but the reality is that it's much more of a "chemical soup" which makes it so.

Although the three "classical water types" (white, black and clear) are used by science to describe many of these habitats, aquarists tend to classify water as "blackwater" or "clearwater", which, although not scientifically "pure", tends to make our understanding and discussions easier!

And the reality is that there are many, many habitats throughout the world which have tons (literally) of botanical materials in them, yet have relatively clear water. It's certainly not a given that the presence of leaves, wood, and other botanical materials in a given body of water will result in brown water and low pH. Rivers like the Juruá, Japurá, Purus, and Madeira) are turbid, with water transparency that varies, and they transport large amounts of nutrient-rich sediments from The Andes. Their waters have near- neutral pH and relatively high concentrations of dissolved solids.

The Rio Xingu and Tapajós are classic examples of "clearwater" rivers. One of the largest tributaries of the Amazon, the "Xingu" has an abundance of rock, and a higher content of dissolved minerals than a blackwater habitat like the Rio Negro. There is not much suspended matter because the rock formations which the river courses through are ancient and no longer erode in the current. The pH varies between 6 and 7.

And, for almost as long as hobbyists have been playing around with "blackwater aquairums", there has been confusion, fear, misunderstanding, and downright misinformation on almost every aspect of them! We’re still seeing a lot of that confusion. It’s important to really understand the most simple of questions- like, what exactly is “blackwater”, anyways?

A scientist will tell you that blackwater is created by draining from older rocks and soils (in Amazonia, look up the “Guyana Shield”), which result in dissolved fulvic and humic substances, present small amounts of suspended sediment, and characterized by lower pH (4.0 to 6.0) and dissolved elements, yet higher SiO2contents. Tannins are imparted into the water by leaves and other botanical materials which accumulate in these habitats.


The action of water upon fallen leaves and other botanical-derived materials leaches various compounds out of them, creating “black-water.” Indeed, this leaching process is analogous to boiling leaves for tea. The leached compounds are both organic and inorganic, and include things like tannin, carbohydrates, organic acids, pectic compounds, minerals, growth hormones, alkaloids, and phenolic compounds.

In summary, natural black waters typically arise from highly leached tropical environments where most of the soluble elements are rapidly removed by heavy rainfall. Materials such as soils are the primary influence on the composition of blackwater. Leaves and other materials contribute to the process in Nature, but are NOT the primary “drivers” of its creation and composition.


So, right from the start, it’s evident that natural blackwater is “all about the soils…” Yeah, it’s more a product of geology than just about anything else. 

More confusing, recent studies have found that most of the acidity in black waters can be attributed to dissolved organic substances, and not to dissolved carbonic acid. In other words, organic acids from compounds found in soil and decomposing plant material, as opposed to inorganic sources. Blackwaters are almost always characterized by high percentages of organic acids.

Interestingly, however, these waters are surprisingly low in dissolved organic compounds (DOC). In fact, Rio Negro black waters are theorized to have low DOC concentrations because of thdiluting effect of significant amounts of rainfall, and because they are diluted by clear waters from nearby systems low in dissolved organic compounds.

Sort of  self-regulating, to an extent, right?

In the podzolic soil where blackwater originates, most of the of the extractable substances in the surface litter layer are humic acids, typically coming from decaying plant material. Scientists have concluded that greater input of plant litter leads to greater input of humic substances into ground water.

In other words, those leaves that accumulate on the substrate are putting out significant amounts of humic acids, as we've talked about previously! And although humic substances, like fulvic acid, are found in both blackwater and clear water habitats, the organic detritus (you know, from leaves and such) in blackwater contains more extractable fulvic acid than in clearwater habitats, as one might suspect!

The Rio Negro, for example, contains mostly humic acids, indicating that suspended sediment selectively adsorbs humic acids from black water.  The low concentration of suspended sediments in rivers like the Rio Negro is one of the main reasons why high concentrations of humic acids are maintained. With little to no suspended sediment, there is no "adsorbent surface" (other than the substrate of the river, upon which these acids can be taken hold of (adsorb).

When you think about it, all of this this kind of contributes to why blackwater has the color that it does, too. Blackwater in the Amazon basin is colored reddish-brown. Why? Well, it has  those organic compounds dissolved in it, of course. And most light absorbtion is in the blue region of the spectrum, and the water is almost transparent to red light, which explains the red coloration of the water!

As we've mentioned many times, water color, although helpful to us aquarists in some respects, is not an absolutely reliable indicator of the pH or ionic composition of the water! There is no substitute for good, old-fashioned water testing!

Remember, just because the water in a botanical-influenced aquarium system is brownish, or has a bit of noticeable "turbidity", it doesn't mean that it's of low quality, or "dirty", as we're inclined to say.  I can't stress it often enough. It simply means that tannins, humic acids, and other substances are leaching into the water, creating a characteristic color that some of us geeks find rather attractive. If you're still concerned, monitor the water quality...perform a nitrate test; look at the health of your animals.


Interestingly (and perhaps, confusingly) the lower section of some Amazonian black-water rivers such as the Rio Negro, Tefé, Uatumã and Urubu in Brazil; Nanay in Peru and some streams in Colombia can have ionic composition and/or pH-values similar to the white water rivers, and not like the typical Amazonian blackwater rivers. It is though by researchers that low electrical conductivity values can be responsible for this phenomenon. 

In addition, it's though that many rivers and streams have to be considered as “mixed waters” resulting from the influence of tributaries with different physical and chemical properties of their waters.

As if we don't need more confusion, right? Talk about "muddy waters!"

So, for us aquarists, the arguments and discussions can rage on and on and on, and aquarists who have been to various parts of these rivers may observe somewhat different characteristics than others...and be 100% accurate in their findings! Generalizations, although often a "no- no", may actually be useful to us. (gulp)

One of the big discussion points we have in our world is about the color and "clarity" of the water in our blackwater aquariums. We receive a significant amount of correspondence from customers who are curious how much "stuff" it takes to color up their water.

Those of us in the community of blackwater, botanical-method aquarists seek out tint and "body" in our water...while the rest of the aquatic world- well, they just sort of... freak the fuck out about that, huh?

Our aesthetic "upbringing" in the hobby seems to push us towards "crystal clear water", regardless of whether or not it's "tinted" or not. And think about it: You can have absolutely horrifically toxic levels of ammonia, dissolved heavy metals, etc. in water that is "invisible", and have perfectly beautiful parameters in water that is heavily tinted and even a bit turbid.

(FYI, WIkipedia defines "turbidity" in part as, "...the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air.")

That's why the aquarium "mythology" which suggested that blackwater aquairums, or aquariums with tinted water were somehow "dirtier" than "blue water" tanks used to drive me crazy. The term "blackwater" describes a number of things; however, it's not a measure of the "cleanliness" of the water in an aquarium, is it?


Color alone is not indicative of water quality for aquarium purposes, nor is "turbidity." Sure, by municipal drinking water standards, color and clarity are important, and can indicate a number of potential issues...But we're not talking about drinking water here, are we?

No, we aren't! 

(And yes, aquariums with high quantities of organic materials breaking down in the water column add to the biological load of the tank, requiring diligent management. This is not shocking news. Frankly, I find it rather amusing when someone tells me that what we do as a community is "reckless", and that our tanks look "dirty."

As if we don't see that or understand why our tanks look the way they do.)

There is a difference between "color" and "clarity."

The color is, as you know, a product of tannins leaching into the water from wood, soils, and botanicals, and typically is not "cloudy." It' actually one of the most natural-looking water conditions around, as water influenced by soils, woods, leaves, etc. is ubiquitous around the world. Other than having that undeniable color,there is little that differentiates this water from so-called "crystal clear" water to the naked eye.

Of course, the water may have a lower pH and general hardness, but these factors have no bearing on the color or visual clarity of the water. And conversely, dark brown water isn't always soft and acidic. You can have very hard, alkaline water that, based on our hobby biases, looks like it should be soft and acid. Color is NO indicator of pH or hardness! Again, it's one of those things where we ascribe some sort of characteristics to the water based solely on its appearance.

As I've mentioned before, a funny by-product of our more recent obsession with blackwater aquariums in the hobby is a concern about the "tint" of the water, and yeah, perhaps even the "flavor" of said water! A by-product of our acceptance of natural influences on the water, and a desire to see a more realistic representation of certain aquatic environments.  

And that means that dark water we love so much.

Yeah, we now see posts and discussions by hobbyists lamenting the fact that their aquarium water is not "tinted" enough. A lot of hobbyists have "bought in" to those mental shifts we keep talking about...

You sort of have to smile a bit, right?

Total mental shift, huh?

We impart color-producing tannins into the water in our aquariums by utilizing leaves and other botanical materials, like seed pods, cones, bark, and even wood. Confusingly, you can achieve the look of blackwater habitats even with relatively hard, alkaline water. Of course, there is more than just the aesthetics, right? Many of these materials will also impart complex compounds, like polyphenols, polysaccharides, lignin, and other substances into the water as well, which can have positive influences on fish health, and the overall aquarium environment. 


So, the approach to create “aquarium quality” blackwater is surprisingly simple, really. Start with high quality RO/DO water, add some botanical materials like leaves, bark or seed pods, and in theory, you’ve created the aquarium equivalent of “blackwater.”  I mean, it’s not quite that simple, as the easy process belies the complex chemical interactions that take place in the water to create these conditions, but for most of us, that’s kind of how it works on a superficial level.

it IS important for us to not delude ourselves into thinking that just tossing some leaves into an aquarium and admiring the tinted color gives us a "blackwater aquarium," like you see in a lot of the so-called "influencer" videos on social media that pop up regularly now. Just sort of "mailing it in" by touching on the most superficial aspects of the concept.

If we throw around ideas like, "The tank in this video represents a blackwater river in Amazonia" or some other such grandiose pronouncement, we owe it to our audience to either try to explain what this means, what the characteristics of a natural blackwater habitat are, or why our tank, filled with lots aquatic plants, gravel, a few leaves, and water of unspecified chemical characteristics isn't "blackwater." It perhaps, superficially, mimics some aspects of the blackwater environment. It's "inspired by..."

But that's it.

And that's okay, but we have a responsibility to our fellow hobbyists to explain this.

To NOT be more accurate in our description about what we do in this sector-to just "cliche" it and label any tank with tinted water a "blackwater aquarium" runs the risk of simply "dumbing down" what we do, and working against the efforts and progress made by so many hobbyists to create a proper, replicable, and consistent methodology to creating botanical-style aquariums.  And it displays a fundamental ignorance of the work of many researchers and scientists, who help classify and study these habitats.

Botanical-method aquariums. Tanks which incorporate botanical materials to influence some aspects of the water chemistry and biology. That's what we play with. Many times, the result is an aquarium with water that has a brownish tint, perhaps a slightly reduced pH, and an array of decomposing leaves and seed pods. 

It's a methodology to create more natural functioning aquariums. It just happens to result in aquariums which look different- perhaps, superficially like blackwater habitats. 

And of course, it's perfectly okay and easy to have an aquarium filled with all of these  tannin-producing materials and to render the water crystal clear with activated carbon or other chemical filtration media! 

And understanding the interactions of these materials with water and the overall aquatic environment in our tanks AND in Nature, have enormous implications for the future of our hobby. 

Water is a sort of "blank canvas"- a starting point...a "media" for our work. So many possibilities...That's the allure of water! 

The beauty of an aquarium is that you can either remove or contribute to the color and clarity characteristics of your water if you don't like 'em, by simply utilizing technique- ie; mechanical and chemical filtration, water changes, etc.

The color of water. It's that simple.

Stay engaged. Stay curious. Stay observant. Stay thoughtful...

And Stay Wet.


Scott Fellman

Tannin Aquatics