June 29, 2020


Just, like...maintain...okay?

We receive a lot of questions about the maintenance of botanical-style aquariums. And it makes a lot of sense, because the very nature of these aquariums is that they are stocked, chock-full of seed pods and leaves, all of which contribute to the bio load of the aquarium- all of which hare in the process of breaking down and decomposing to some degree at any given moment.

It's not so much if you have to pay attention to maintenance with these tanks- it's more of a function of how you maintain them, and how often. Well, here's the "big reveal" on this: 

Keep the environment stable.

Environmental stability is one of the most important- if not THE most important- things we can provide for our fishes! To me, it's more about doing something consistently than it is about some unusual practice done once in a while.

Like, ya' know- water exchanges.

Obviously, water exchanges are an important part of any aquarium husbandry regimen, and I favor a 10% weekly change. Iit's the regimen I've stuck with for decades, and it's never done me wrong. I think that with a botanical influenced aquarium, you've got a lot of biological material in there in addition to the fishes (you know, like decomposing leaves and softening seed puds- stuff like that), and even in well-managed, biologically-balanced aquarium, you still want to minimize the effects of any organics accumulating in a detrimental manner. 

This piece is not really about water changes, and frankly, you can utilize whatever schedule/precentage works for you. The 10%-20% weekly has worked for me; you may have some other schedule/percentage. My advice: Do what works for you and adjust as needed.

Just do something.

Another question that we hear all the time around here is wether we should let the leaves in our tanks remain as they decompose completely, or remove them after they begin to break down.

Depending upon my "mood de jour", I may elect to keep leaves and botanicals in my system until they completely decompose. Ing an otherwise well-managed aquarium, this is generally not a water-quality-affecting issue, in my experience, and is more a matter of aesthetic preferences. There are times when I enjoy seeing the leaves decompose down to nothing, and there are other times when I like a "fresher" look and replace them with new ones relatively soon.

Some individual leaves and botanicals "recruit "an inordinate amount of biofilms, which even I may find distracting (hard to believe, I know...), so I will typically remove those "offenders". Again, no harm in leaving them in; the presence of biofilms indicates the presence of beneficial bacteria just doing their thing. It's just that sometimes, you don't want them doing too much of their thing- or in a place where you have to look right at it every day! You can remove sections of it with a planting tweezer (tedious, but oddly relaxing and satisfying, I might add), or a siphon. Of course, as mentioned above, you can just yank the offending botanical right out of the tank and be done with it, too!

When leaves and botanicals break down completely, you end up with a fair amount of "stringy fungal growth, biofilms, and fine particles of decomposed leaves that tend to accumulate here and there in healthy aquariums.

What's cool about this stuff is that, not only do you see it in aquariums- you see it extensively in natural ecosystems, such as Amazonian streams, Asian peat swamps, and other habitats.

Of course, in the case of a "botanical" style aquarium, It's an integral component of  what we call an "enriched" substrate. As botanicals break down- just like in Nature- they create a diverse matrix of partially decomposing plant materials, pieces of bark, bits of algae, and some strings of biofilm.

Ahh, "detritus..."

Stuff that sounds diverse, and it's also benign. Of course, in the aquarium hobby, it's all classified as "detritus." Detritus seems to have a bit more of a sinister connotation to it. 

The definition is a bit more precise:

"Detritus is dead particulate organic matter. It typically includes the bodies or fragments of dead organisms, as well as fecal material. Detritus is typically colonized by communities of microorganisms which act to decompose or remineralize the material." (Source: The Aquarium Wiki)

Well, shit- that sounds bad! 

It's one of our most commonly used aquarium terms...and one which, well, quite frankly, sends shivers down the spine of many aquarium hobbyists. And judging from that definition, it sounds like something you absolutely want to avoid having in your system at all costs. I mean, "dead organisms" and "fecal material" is not everyone's idea of a good time, ya know?

Literally, shit in your tank, accumulating. Like, why would anyone want this to linger- or worse- accumulate- in your aquarium?

Yet, when you really think about it and brush off the initial "shock value", the fact is that detritus is an important part of the aquatic ecosystem, providing "fuel" for microorganisms and fungi at the base of the food chain in aquatic environments. In fact, in natural blackwater systems, the food inputs into the water are channeled by decomposers, like fungi, which act upon leaves and other organic materials in the water to break them down. 

And the leaf litter "community" of fishes, insects, fungi, and microorganisms is really important to these systems, as it assimilates terrestrial material into the blackwater aquatic system, and 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!

That sounds all well and good and well, grandiose, but what are the implications of these processes- and the resultant detritus- for the closed aquarium system?

In years past, aquarists who favored "sterile-looking" aquaria would have been horrified to see this stuff accumulating on the bottom, or among the hardscape. Upon discovering it in our tanks, it would have taken nanoseconds to lunge for the siphon hose to get this stuff out ASAP!

In our world, the reality is that we embrace this stuff for what it is: A rich, diverse, and beneficial part of our microcosm. It provides foraging, "Aquatic plant "mulch", supplemental food production, a place for fry to shelter, and is a vital, fascinating part of the natural environment. 

It is certainly a new way of thinking when we espouse not only accepting the presence of this stuff in our aquaria, but actually encouraging it and rejoicing in its presence! 


Well, not because we are thinking, "Hey, this is an excuse for maintaining a dirty-looking aquarium!"


We rejoice because our little closed microcosms are mimicking exactly what happens in the natural environments that we strive so hard to replicate. Granted, in a closed system, you must pay greater attention to water quality, but accepting decomposing leaves and botanicals as a dynamic part of a living closed system is embracing the very processes that we have tried to nurture for many years.

And it all starts with the 'fuel" for this process- leaves and botanicals. As they break down, they help enrich the aquatic habitat in which they reside. Now, in my opinion, it's important to add new leaves as the old ones decompose, especially if you like a certain "tint" to your water and want to keep it consistent.

Not only does adding new leaves keep the water tint (and parameters, once you dial 'em in) consistent, it also gives you a sort of "evolving" aesthetic, which is similar to what you'll see in Nature: newly fallen leaves replacing older ones that have decomposed. Botanical system can be very dynamic in this way!

And then, there's that whole "water color" thing...

Like many of you, I store my water in plastic containers for use during water changes. Over the years, I've sort of worked out a rough "formula", if you will, to create consistent "tint" and conditions for my makeup water. Typically, I'll add 3 medium-sized Catappa leaves to a 5 U.S. gallon container of RO/DI water. This has always given me a nice even color and a pH around 6.5-6.6, which is the range I maintain in my display aquariums.

Hardly an exact science, I know.

Now, "your mileage may vary" as they say, and perhaps a different number of leaves in a different sized container works for you. Obviously there are many variables, even in as simple a practice as steeping leaves in your makeup water, like the source of the leaves and their "potency" (in regard to tannins contained in their tissues), the age and condition of the leaves, temperature, etc., etc., etc.

Oh, and then there's that recommendation to test your water. Yeah, that's me. And you don't need to go crazy, but regular tests of pH, alkalinity are really important when you're flirting with soft, acid water systems. And checking phosphate and nitrate are never a bad thing, as they can give you an insight into trends within your system, as well as just good old-fashioned knowledge about how your system tends to operate once it settles in.

Although it IS possible to have too much information (to the point where you can obsess over what are really insignificant details), it's never a bad thing to have enough to spot trends, right?

People ask a lot if blackwater tanks are tricky to maintain, given the reputation for challenges in low pH, soft water systems and the more delicate fishes traditionally associated with them (like Discus and Wild Angelfish, etc.). Honestly, I don't think they are any more "difficult" to care for than any other type of aquarium.

Definitely easier than say, a Rift Lake cichlid tank- and a magnitude easier than a full-blown reef system (or coral propagation facility, as I can attest to!). Like anything else, you'll develop the techniques, skills, and systems to manage your system in a manner that works for you and your fishes- and that's really all you need to do, in my opinion!

Observation- just looking at your fishes and their aquariums- goes a long way towards success in ANY type of aquarium. With hobbyists busier than ever before, with more personal and other demands vying for attention, this obvious thing may not be as easy as it used to be- so make it a point to spend some time every day just looking at your aquarium.

The longest I've personally maintained such a system has been about 5.5 years, and the only reason I broke down that aquarium was because of a home remodel that required the removal of everything from the space in which the aquarium was located. I set it up again shortly after the work was completed. The reality, though, is that I could have kept this system going indefinitely. 

As most of you who work with these aquariums know, the key to long-term success with them is to go slowly, deploying massive amounts of patience, common-sense husbandry, monitoring of environmental parameters, and careful stocking management. Not really much different from what you'd need to do to successfully maintain ANY type of aquarium for the long haul.

Yeah, real "news flash" there, right?

So, it all starts with the way these tanks "run in", and that will sort of "set the tone" for the care and long-term maintenance involved. 

Expectations, if you will.

First off, one of the things that we all experience with these types of systems is an initial burst of  tannins, which likely will provide a significant amount of visible "tint" to the water. If you're not using activated carbon or some other filtration media, this tint will be more pronounced and likely last longer than if you're actively removing it with these materials! And, if you use too much carbon, you'll be one of those people who emails me with a starting line like, "...and I added an entire package of catappa leaves and my water is barely tinted..."

You might also experience a bit of initial cloudiness or turbidity...this could either be physical dust or other materials released from the tissues botanicals, or even a burst of bacteria/microorganisms. Not really sure, but it usually passes quickly with minimal, if any intervention on your part. Oh, and not everyone experiences this...often this is a phenomenon which seems to happen in brand new tanks...so it might not even be directly attributable to the presence of the botanicals (well, at least not 100%). Could be the sand, or other dust/dirt from the other hardscape materials or the tank itself.

Oh, and the reality is that in a tank with lots of botanical materials, the water may not always be "crystal clear." I mean, sure it'll be clear- as in, you can see across it- but it might have a sort of "soupy" look to it. This is for the very reasons stated above. Mental shifts required...

So, that being said...what happens next?

Well, typically, as most of you who've played with this stuff know, the botanicals will begin to soften and break down over a period of several weeks. Botanical materials are the very definition of the word "ephemeral." Nothing lasts forever, and botanicals are no exception! Pretty much everything we utilize- from Guava leaves to Melostoma roots- starts to soften and break down over time. Most of these materials should be viewed as "consumables"- meaning that you'll need to replace them over time.

I'll backtrack and touch on that whole idea of "leaving stuff in" to break down fully.

I have never had any negative side effects that we could attribute to leaving botanicals to completely break down in an otherwise healthy, well-managed aquarium.

Many, many hobbyists (present company included) see no detectable increases in nitrate or phosphate as a result of this practice. Of course, this has prompted me to postulate that perhaps they form a sort of natural "biological filtration media" and actually foster some dentritifcation, etc. I have no scientific evidence to back up this theory, of course (like most of my theories, lol), other than my results, but I think there might be a grain of truth here!

So, the living with your botanical-style backwater aquarium isn't just about a new aesthetic approach. This is where the "mainstream aquarium crowd" (LOL) gets it all wrong and really "short-sells" this stuff... It's about understanding and processing what's happening in the little aquatic ecosystem you've created. It's about asking questions, modifying technique, and, yeah, playing hunches- all skills that we as hobbyists have practiced for generations.

When you distill it all- we're still just "keeping an aquarium"-but one that I feel is a far more natural, dynamic, and potentially game-changing style for the hobby.

So, relax, observe, and...just maintain. Your aquarium will be fine.

Stay diligent. Stay consistent. Stay aware. Stay involved...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


June 26, 2020


Ever more accurate...

There are some things that we as botanical-style aquarists are starting to figure out, aren't we?

We're learning how to work with botanicals as never before, and making great strides at understanding and attempting to replicate the unique natural aquatic habitats from where our favorite fish come from. 

We're becoming ever more accurate at replicating them in a "functionally aesthetic" way. Different than what's been done in years past, IMHO.

After decades of playing with botanicals, and after five years of building Tannin Aquatics, I've formulated a fair amount of opinion on some of this stuff, as you might guess! 

fIn recent years, I've fielded questions from all sorts of hobbyists and representatives of various biotope aquarium contests and groups, which seem to have similar "themes", and I feel that there are some things which need to be clarified about the idea of how we represent natural habitats in our aquariums.

I mean, sure, one could say I'm a bit biased because I own a company which offers natural materials from around the world to enable hobbyists to replicate -at least on some level- the aesthetics- and more important- some of the function- of various aquatic habitats from around the world, and that I want to justify offering stuff that merely "represents" the materials found in the ______ region.

(Damn, that's a fucking mouthful, huh?)

I'll give you that.

And yeah, my orientation- my personal passion- the passion which led me to found Tannin Aquatics- was to curate, love, and offer my fellow hobbyists the natural materials they can use to create inspiring and compelling natural-style aquariums. To what level of authenticity we all aspire to is the choice of each one of us as individuals.

Where I take issue- like so many things in this hobby- is with attitudes. I mean, I've had people "call out" others because one of the leaves or whatever in a "Rio____ biotope aquarium" is "not endemic to the region", or whatever. I see hobbyists get trashed hard by others over stuff like that on a fairly regular basis.

Okay, I get your thinking, but really...

Even with the biotope aquarium contest winners, you can take this attitude and nitpick everything to the "nth degree":

I mean, what about the substrate?

Is it absolutely Rio Negro region "podzol" from the Andes? Is every species of wood used in the tank form the surrounding varzea forest? Or, is it just packaged aquarium sand...(gulp!)? Is every freaking bacteria, fungi, Paramecium, etc. the exact species that comes from the region being represented?

Huh? Is it? 

How crazy do we want to go when criticizing the efforts of others- and to what purpose?

Can these "armchair critics" really discern the decomposing leaf of Hevea brasiliensis, Swietenia macrophylla, or Euterpe precatoria from Catappa, Guava, Jackfruit, Apple, Oak, etc? I mean, seriously? I mean, I can't, and I work with this stuff every single day of my life...How can they? And, if someone cannot source these specific Amazonian leaves or seed pods, does that "invalidate" the aquarium from consideration as a "biotope aquarium?"

Does it even matter?

Whew, I AM getting worked up here, lol.

Again, it's the self-righteous attitudes surrounding these kinds of things that drive me crazy...And granted, these are extremes and not everyone who works in the biotope aquarium field or judges one of these contests is a straight-up douchebag. Most are simply knowledgable, well-intentioned hobbyists and scientists who want to see aquariums which represent the wild habitats as accurately as possible...

The point of my rant is that I think we all want the same thing.

We all want to represent. as accurately and faithfully as possible, the biopic niches we're into. And that is incredibly cool! But when we get caught up in semantics and petty arguments for the sake of...well, for the sake of "being right"- who does this help? Who does it hurt?

Doesn't this kind of criticism hurt those who are in a unique position to use their aquarium hobby talents to maybe, MAYBE reach a few non-hobbyists with their beautiful tank...perhaps raising awareness of the plight of that Borneo peat swamp or African flood plain? Does it discourage them from trying again in the future and sharing their work with the world?

Yeah. I think it does. And that sucks.

We need to lose the attitude on this topic.

I think many aquariums can be accurately labeled "biotope-inspired" or "biotope-style" aquarium. I think a lot of the cool work our community does is at that level. There is nothing wrong with that at all.

Think about more than just the look...think about how these aquariums FUNCTION over an extended period of times with all of these natural materials present...

THAT is the key. 

Not stressing out or attacking others because the aquarium doesn't have the exact seed pod that might be found in that garage which the hobbyist or contest entrant is trying to represent. I am passionate about this, because I receive way too many emails from hobbyists who are desperately searching for ________ pods or ________ leaves to fit these "requirements" forced on them...or at least, which they feel are being forced upon them!

I feel that more clarity and flexibility is required.

As I've indicated before, much of our materials originate from multiple geographic regions around the world, having been transplanted by man, although the "type specimens" of a given botanical (rather, the plant it is derived from) are found in a specific region. Examples would be Catappa and Guava, which are found all around the world, having been transplanted by man for centuries.

And I'll hazard a guess that most "critics" and "judges" in biotope competitions couldn't distinguish between another species of Artocarpus or a Jackfruit leaf, or a Yellow Mangrove from a Red Mangrove, or a Live Oak leaf, once they've been down for a while!

Same with botanicals...

So, the idea that the materials we offer and use represent many of the things found in natural waters is important to consider. Now, I would never discourage those who want 100% accuracy to pursue it; and I certainly offer not criticism of this desire. 

Yet, I think we need to still be a bit open-minded, in terms of what we use in our tanks to represent materials found in a given aquatic habitat.

This gives you a certain degree of "flexibility", in terms of what botanicals you can use in a given setup.

A lot you ask for materials that would be found in an "Asian blackwater pond" or a "South American rain forest stream"- more or less broad geographic descriptors, but we understand the desire to be a bit more accurate, particularly for more hardcore biotope enthusiasts and hobbyists entering competitions. 

I feel you.

We have made the attempt in our product descriptions to describe the point of origin or the botanical wherever possible, to give you some sort of a "guide" should you need it.

In the end, however, it's important to note that many of our botanicals should be thought of as "reasonable facsimiles" to the materials found in the wild aquatic habitats of the world. We think we have possibly the most comprehensive collection of botanical materials, curated and tested for safe use in aquatic displays- ever assembled in one place!

(when our supply chain isn't disrupted, that is! 😂)

Of course, it's nothing compared to what Nature deposits in the waters of the world, but it's a good start! We can't offer it all, but we can offer some of it!

So, it goes without saying that we feel a little bit of  "flexibility"- using what's available to represent whats out there- isn't a bad thing!

I'll tell you that most any of the natural materials we offer are okay for a variety of species of fishes. The qualifier is that most of the stuff we offer (botanicals and leaves, in particular) are geared towards fishes which come from aquatic habitats other than super-specialized environments like the African Rift Lakes, which are hard, alkaline lakes with more rock and sand than wood and leaves.

We have broken down our classifications of natural materials on our website into categories such as leaves, seed pods, stems and bark, and substrate additives. If you read our descriptions carefully, we try to provide not only the scientific name of the botanical in question, but the geographic origin if known. This is somewhat important for those of you who require the most geographic accuracy possible.

Ever more accurate.

Most of our items, however, fall into that category we've often referred to (rather unprofessionally, I must confess) as "generic tropical"- stuff that represents the materials you might find in tropical aquatic ecosystems around the world.

In other words, the cool-looking Cariniana pod from the Cariniana legalis tree of South America would be perfectly at home in an Amazonian-themed aquarium. It would also be perfectly acceptable in a Southeast Asian or African-themed tank, as it resembles some of the botanical materials that are found in the aquatic habitats of these regions.

"Generic Tropical."

Yeah, this concept might make a few hardcore biotope enthusiasts cringe.

However, I've seen dozens of biotope aquariums in big competitions representing very specific Asian or South American habitats, with substrates covered in Beech or Oak leaf litter from Europe or North America, and no one- judges included- batted an eyelash, so...

I'm just sayin'.

IMHO, we shouldn't get too bent out of shape about this.

The reality is that most of the materials which accumulate on the substrate or elsewhere in the aquatic habitats we try to recreate either were there to begin with (as in the case of the flooded igapo forest floors of South America), or fell into the water from overhanging vegetation, or were swept up by flooding, wind, or other natural events.

There is not some set model for how these materials arrive into aquatic habitats. And, to be objective,  I have to proffer that many of the materials that we offer for this purpose are from trees and shrubs often not found directly in the path of water.

Maybe they're from areas nearby.

Some are from mountainous regions or plains which don't have bodies of water in the vicinity that they're found. Again, they are selected for inclusion in our offerings because they have an appearance or characteristics which  represent those of materials that we've seen in various aquatic habitats.

Key word here: "represent."

"Generic tropical."

A perfect descriptor, IMHO

And of course, if you want to really "split hairs", you could say "generic aquatic", because several of the materials which we offer are from temperate regions of the world, too!

It all goes back to the level of authenticity that you are striving to achieve.

And some tropical-derived materials from one part of the world are perfectly suitable for- and I'd argue, indistinguishable from- from materials found in other regions of the world.

Yet they work perfectly in aquariums to represent them.  

As for obtaining the EXACT materials that you'd find in the habitats you're interested in? 

Keep striving. DO the ground work- you can get creative in sourcing some of them.

We spend enormous amounts of time trying to work with suppliers worldwide to source new and more "geographically specific" botanicals. Often times, local governments impose strict export restrictions on any significant quantity of some of these items, and to obtain them in quantities is simply not practical or legal. Others are very uncommon. Still others have species in their family which can represent them in appearance, function, etc.

My advice?

Don't stress over it. Enjoy it.

Incorporate the function and aesthetics from materials which represent those found in our favorite tropical aquatic habitats. Learn about the habitat, and how materials accumulate in the waters- and how they influence the fishes that live in them.

It's a fascinating pursuit in and of itself!

So, in summary, we may not always be able to offer the exact botanical materials that you see in the videos and pics you find, but most of the botanicals we offer are good representative of the materials you see in the wild aquatic habitats. I personally have spent many hours over the years studying photos and videos and getting a lot of inspiration for the types of things we elected to offer at Tannin.

You should, too.

Because you'll learn to appreciate the power of "generic", while striving to be ever more accurate in creating aquariums which replicate the look and function of the wild aquatic habitats we all love so much.

Stay creative. Stay resourceful. Stay disciplined. Stay calm. Stay happy...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

June 25, 2020


You're not just an aquatics businessperson- You're a "bricoleur!"

I am anything but some "business guru."

Yet, for some reason, a lot of people in the aquarium industry reach out to me with questions about how to start or innovate their aquatics businesses, online or brick-and-mortar. I find this very flattering, and humbly accept the accolades I receive. Happy to help others when I can.

That being said, I find it astounding that I- the guy who sells "twigs and nuts" for a living, is seen as some kind of source for aquatics business knowledge. And just recently, I received an email from a fellow aquatics industry vendor the other day (who operates in a completely different sector of the industry than I do), just worried sick about some newcomer to his niche. 

He raised questions which I find to be surprisingly common in a lot of industries (yeah, not unique to our wet and stinky businesses!), but which I am asked a lot by aquatics industry peeps. Most of them concern what to do when other guys arrive on the scene. 

I think we make waaaay to big a deal about this. 

Nonetheless, it comes up often enough in inquiries that I should address it in a blog (Oh, lucky YOU!)...

As usual, this answer sort of requires me to look into my own attitudes and experiences, to give context to it. 

It makes me think back to when I first started Tannin in 2015. A far cry from the cranking coral propagation business which I sold my share of when I pushed out to start Tannin.

That scene was jumpin!'

And, the botanical-style aquarium scene?

Well, there was no "scene."

It was a completely uncharted territory.  

The word "botanical" ( now pretty much the accepted, standard descriptor for all of this stuff we toss in our tanks) simply didn't exist in this context at the time. So, we started by appropriating that term, to give context to the "lawn trash" that we worked with. That was a good start! The term sticks to this day, and is used widely in our little hobby niche.

Off we went.

We got really busy "scratching our own itch", creating a business around a problem that I had- not being able to find a reliable source for the leaves and twigs and such needed to create botanical-style blackwater aquariums!

What to do?

I turned to...bricolage!


“Bricolage is a term used to describe the process of using whatever tools and processes are immediately available. The concept is most immediately familiar to fine artists, and implies a sort of combination of practicality and craftsmanship.

As botanical-style aquarium lovers, we've all learned to engage in this process almost from the get go. Yeah, we're "bricoleurs"- hobbyists who create using whatever is available to us.  We're a lot luckier now- obtaining botanical materials is easier than ever, with multiple vendors and online resources that simply didn't exist all that long ago. For many years, there wasn't a consolidated source of botanical materials for use in aquariums. We, as creative hobbyists, had to research, procure, and test these things for ourselves.

It was a bit of a challenge. yet, I used my skills as a bricoleuer- someone who makes use of whatever is available- to get this thing off the ground.

As a startup business, Tannin was able to immediately address the problem.  Having worked in the coral propagation and importation business for several years, I got pretty good at sourcing stuff from exotic places around the world. Although it took some time and travel, I was able to build upon a trusted supplier network  of botanicals  surprisingly quickly.

Of course, if I actually wanted to make a living at this, I also had to find all of the other crazy hobbyists who were into this sort of shit! And I had to educate those who weren't, dispel many myths, misunderstandings, and outright lies about these types of tanks in the process.

We had to procure stuff, test it, utilize it, share our experience, develop technique, refine it, and figure out a way to effectively market it and offer it to the hobby.

In short, we had to do everything from scratch!


That was not only rather difficult- it was also one of the most enjoyable things I've ever done in business! Yeah. And we have made a bit of a difference, and I'd like to think that we still are! At the very least, it's not as much of a challenge for hobbyists to get into these types of tanks, learn about the wild habitats,  grab botanicals, and to find out more about them.

On the other hand, it's still a bit of a challenge for the consumer, when you think about it. Other vendors have arrived on the scene, offering more places for hobbyists to do business with. With more choices come more decisions, considerations- and friction- for hobbyists.

What makes one source better than the others? I mean, a leaf is a leaf, right? (Well, not necessarily- quality is apparent...but there's more to it, of course)

Here is the "meat" of my answer for this guy and other vendors who worry about it:

Yeah- with more interest, more vendors, and more hype about botanical-style aquariums in general, there is a lot more "noise." Meaning, of course, a lot more B.S. to filter through...a consistent lack of information (with a few exceptions), and not a huge body of recent firsthand experience with botanical-style tanks for newbies to draw upon.

What's happened in our little sector is that people are seeing an easy way to make a few bucks, push out some stuff, and try to run a "business" - enterprising and admirable to some extent, but incredibly short-sided in other ways.

Now, lest you see this as a jealous rant by a vendor who doesn't want any competitors- you're missing the point. 

My "business sense" always sees this as a sort of opportunity! Yeah, and opportunity to improve what I do, and to get better and further distinguish Tannin from any erstwhile "competitors" in the process- without stressing out about THEM.

Yeah. I can't waste mental "capital" worrying about the latest leaf vendor. There were guys selling them before I arrived on the scene, and they'll be more of them after I retire. 

To be perfectly honest, I really don't care about other businesses that sell botanicals. Seriously.  None of them are a perceived threat to me. I'm too busy trying to be a threat to myself! I spend more time trying to put myself out of business than I do worrying about some e-Bay startup selling seed pods or leaves. I spend a lot of time looking at what I feel are weaknesses in our business...from a product, customer service, branding, and information distribution standpoint. I have enough to worry about without thinking about the latest "leaf vendor" out there.

This is something that those of you in the aquatic business need to think about more. If you're good enough, you'll get yours. If you suck, you'll lose. Period. Don't suck. I have friends in various segments of the aquarium industry who simply freak the fuck out every time a new guy comes into the game. This, in my opinion, is an absurd waste of time and energy.

Don't do that.

The reality is that: a) if you're good enough, you'll always find-and keep new customers,  b) it's incumbent upon YOU to constantly tweak and improve your business to take care of them, and c) there is always stuff you can do to innovate, refresh, and maintain your market share.

Quite honestly, in my sector, I see the fact that new businesses are arriving as proof that we have a good market- with enough interest to sustain multiple businesses.A real validation! An opportunity to improve MY business- not as a response to a threat- but as an evolution necessitated by change in the market (ie; more homogenized vendors). And you do have plenty of options, even in a crowded market with "insurgent" newcomers, right?

Yeah, you can always do one of these seven things:

1) Go about making your business the best it can be, innovating and pushing forward, while building your community and brand. Keep your head down and push forward. Sure, have some awareness of what's going on, but don't drive yourself nuts.

2) You can reach out to the new guys and forge some sort of strategic partnership of some sort ("Hey, you are really good at selling _________, and I'm good at selling__________- let's see if we can work together...")

3) You can pivot to some new niche or speciality within the industry. Sometimes, this is a challenge- or a blessing.

4) You can vow to be the meanest guy around and simply figure out ways to destroy the competition via price cuts, better distribution, or whatever aggressive tactics soothe your ego.

5) You can simply buy out your emerging competitors. Yeah, just throw cash at them. Peace out, bitches! 

6) You can welcome the new guys and challenge them to contribute to the community that you've helped build and serve. You'd be surprised how well this can work. The good guys will jump on this and you'll make terrific friends, working together to grow the sector that you operate in, resulting in better business for everyone- including the consumers. The losers will just continue to sell stuff and offer little more- ultimately "commoditizing" and devaluing their product- and self-limiting themselves from relevancy in the process.

7) You can get angry, grab your toys and leave the metaphorical sandbox. Pack it in. Fold, like a cheap chair...Just quit.

Obviously, these recommendations cover the gamut, and you're likely to do one of them- or some combination of them, in a manner which suits you. I personally hate recommendation number 7, but a lot of people do select that option. 

The reality is that you simply need to worry about YOUR business, and obsess over what you do. Although I admit, I do occasionally glance over the shoulder to see what's up in my sector. I'd be foolish NOT to do that once in a while. You have to at least be aware of stuff. An ongoing sort of "rule of thumb" here at Tannin is that, if we see a "competitor" doing something similar to what we do, it's time to stop doing it. And funnily, often times we simply stop doing it for our own reasons, and coincidentally find that the competition just started doing it!


Remember we had like, 15 different "variety packs", each with different botanicals? It was maddening, developing "recipes" for each, maintain appropriate inventories of botanicals for them, and generally keeping up...Plus, we learned from market feedback that our customers preferred making up their own quantities of these things, preferring "recommendations" and the freedom to select from a whole range of stuff in quantities that THEY needed rather than set packs. What we call "curated themes" arose. 

So we killed the "variety packs" in 2018. Good riddance, indeed.

And hilariously, almost every time a new competitor comes on the scene, they offer "variety packs" of botanicals, and I wonder, just a for a second- how long they'll be able to do that while growing their business and keeping their sanity! Maybe they can. I know that we can't..and our customers and my staff are delighted for that. Besides, we have the super popular "Enigma Pack" if people want us to curate for them!


Constant, relentless effort to innovate, craft, work with what you've got, to improve and drive your business forward- regardless of what the competition is trying to do. Don't listen to the accolades, and don't get taken down by the criticisms. March to your own drummer. Work with what you've got. Move forward- in a manner that works for YOU. If you've got something people want, the market will decide, and you'll win. If you don't...well, you still have options, right?

So, that's today's slightly long-winded answer to an oft-asked aquatics business question. Gotta run now..I have some new products to attend to! 

Don't stress out over this stuff. Enjoy the process.

Stay innovative. Stay unabashed. Stay unique. Stay diligent. Stay creative...

And Stay Wet.


Scott Fellman

Tannin Aquatics 






June 24, 2020


"Passive management" and the evolving aquarium...

Have you ever considered the "lifetime" of an aquarium?  I mean, does an aquarium HAVE a lifetime? Or will it just go indefinitely if we let it?

What does that even mean, in aquarium terms?

I like to think about aquariums as I do a garden.

Yeah, aquariums are very much like terrestrial gardens.

They have 'ebb and flow" (literally, in some cases!), growth, challenges, and dieback..they have setbacks- and rebounds. I'll bet that if you tracked what happened in a "community aquarium" over the course of say, two years, what you end up with after two years may be significantly different than what you started with. 

In a reef aquarium, where corals are competing for light, nutrients, and space, this type of "evolutionary" change takes place. It's near constant, and it can be quite profound.

Oh, sure, some of the changes that occur during the "life" of an aquarium are human-imposed, such as equipment modifications/replacements, aquascaping "edits", fish and plant additions, etc. However, if you look carefully (as I'm sure that you do), as many changes can be attributed to the cycle of life which occurs in your little microcosm as to human "intervention" of the aquarium environment. 

Things like the growth and/or "dieback" of plants, the proliferation of algae, the gradual decay of wood and aquatic botanicals, social hierarchies among inhabitants, the "patina" of biofilm/algae, however subtle, that makes fresh aquarium substrate "matte out" over time, looking more natural, more subtle...more full of life.

What the Japanese call "wabi-sabi"- the transient nature of things- is both beautiful and inevitable.

And change doesn't happen uniformly, either.

I remember from my experience growing corals commercially, that on any given day, some of the many thousands of specimens we had growing in our facility would be struggling. Some would be absolutely cranking!

Others would be just sort of "there."

And it would change constantly. It was a great demonstration for me of what aquatic husbandry is all about. You need to observe, tweak, and sometimes, simply get out of the way.

The science is one thing.

You learn "best practices" and protocols very quickly, and adhere to them. The "art" of being an aquarist- the really tricky part of this game- is how we choose to manage this multifaceted microcosm, with all of its "moving parts" and subtle complexities.

We can let things decline. Or, we can take charge and attempt to stave off the inevitable. Botanical-style aquariums offer numerous opportunities for making changes- or not.

How we as humans choose to accept this progression and change is purely based on our own tastes.

The reality is that these things will continue despite any interventions we perform on our tanks. We can "resist" them, performing "maintenance" takes on our tanks, like trimming plants, fragging corals, scraping algae, stirring the top layers of substrate, etc.- but these are merely serving to counteract or stave off the inevitable changes that occur in an aquarium as it establishes itself, begins to thrive, and gradually declines.

Of course, in many cases, the "decline" is so gradual, so subtle, that the outsider hardly notices.  In the case fo a botanical-style aquarium, with its abundance of seed pods, leaves, and other materials, you'd be hard-pressed to really call it a "decline." It's more like an evolution, really.

You, the aquarist, ever keen on anything that occurs in your tank, will notice- and often perform subtle (or not-so-subtle) interventions to counteract this process, lest it descend into some sort of chaos, right? 

Yet, isn't "chaos" sort of a human-ascribed thing? I mean, we're talking about changes in the aquatic habitat which evolve the look and perhaps the biological "operating system" of the aquarium. This is absolutely analogous to what happens in natural aquatic systems.

Stuff breaks down, and different types of organisms flourish and reproduce as a result. Nothing goes to waste in Nature...and that includes the "nature" which is found in our aquariums, too..If we allow it to happen.

It's entirely possible, in my humble opinion, that we, as aquarists actually sabotage the essential natural processes which help our tanks run when we attempt to "intervene" through excessive maintenance.

Perhaps a hands-off approach- "passive management", if you will- is not always a bad thing.

I sometimes wonder what our aquariums would evolve into over the course of a couple of years if we merely performed basic maintenance tasks, such as water changes, equipment maintenance, feeding, scraping the viewing panels, etc., and did little else. No animal replacement. No trimming of plants, fragging of corals, or removal of fish fry. No rearranging of the aquascape. 

What would you end up with?

Of course, the answer depends upon what the "end point" is. For that matter- does there have to be one?

It seems that in recent years, I've executed more aquariums in a shorter period of time than ever in my aquatic career. Unusual for me, because, as you might imagine- I'm kind of a "leave the tank be" kind-of-guy.

One of the ideas we play with quite a bit is hardly "radical" in it's departure- you've likely done a version of this hundreds of times during your aquarium hobby career: It's the idea of keeping your aquarium more-or-less "intact" while moving on to a new iteration.

In other words, you're kind of over your Southeast Asian Cryptocoryne biotope, and ready to head West to South America. So, rather than tearing up the entire tank, removing all of the plants, the hardscape, the leaves and botanicals, and the substrate, you opt to remove say, only the plants and the driftwood/rocks from the tank; exchange a good quantity of the water.

Woooah! Crazy! Fellman, you fucking rebel...

I know. I know. This isn't exactly earth-shattering. 

On the other hand, in the world of the botanical-style aquarium, the idea of leaving the substrate and leaf litter/botanical "bed" intact as you "remodel" isn't exactly a crazy one. And conceptually, it's sort of replicates what occurs in Nature, doesn't it?

Yeah, think about this for just a second.

As we almost constantly discuss here, habitats like flooded forests, meadows, vernal pools, igarape, and swollen streams tend to engulf 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.

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.

Leaves begin to accumulate. Detritus settles.

Soils dissolve their chemical constituents- tannins, and humic acids- into the water, enriching it. Fungi and micororganisms begin to feed on and break down the materials. Biofilms form, crustaceans multiply rapidly.  Fishes are able to find new food sources; new hiding places..new areas to spawn.

Life flourishes.

Nature doesn't "edit." She evolves.

Could you resist "editing" your aquarium for a period of time? Would you want to? Is rearranging stuff and re-working things as much part of the hobby as just looking into the tank and enjoying it?

And if you went completely "hands-off" with your tank, what would happen?

No one said the hobby is easy, but it’s not difficult, either- as long as you have a basic understanding of the environmental processes and conditions within your aquarium. And the idea of leaving essential biological components of your aquarium more-or-less "intact" for an indefinite period of time is really compelling.

What would happen?

Would anarchy reign, or would a different sort of system ultimately evolve? Would it succeed on some level that you wouldn't have considered previously? What would come to dominate, and what would fade away?

How would Nature work with what you gave her in your little glass or acrylic world called "an aquarium?"

How would "passive management" affect the dynamics of this microcosm?

Fun questions to ponder. Perhaps.

Stay  curious. Stay thoughtful. Stay engaged. Stay full of wonder. Stay passive?

And Stay Wet.


Scott Fellman

Tannin Aquatics.



June 22, 2020


Sifting through the sediment: The thinking behind "NatureBase" substrates...

"Some sediment and sand, meet in a river, and..."

Wow, sometimes, you start realizing that what you've been obsessing about for so long might actually be interesting to other people, too! Last week, I started talking a bit more specifically about the specialized substrates that I've been working on for the past couple of years, around a month out before releasing them- and the response has been nothing short of crazy...And it taught me some things- well, reinforced some things- which I believe in. specifically:

1)There is a hunger for new and unique aquarium substrates . 

2) Aquarists are ready for something new, that is not just about the "look", and are willing to be a bit adventurous...

3)Those of us in the industry have been doing a sort of lackluster job on creating exciting new products for aquarists.

And I'm not trying to sound like an arrogant jerk here. I'm making some observations and sort of confirming my "thesis" about this stuff. Let's look at this a bit more, and maybe give a bit more context on our "NatureBase" range of substrates.

Now, first off, I started playing with substrates a few years back, mainly because I couldn't find exactly what I was looking for on the market. This is not some indictment of the major substrate manufacturers out there...I LOVE most of them and use and happily recommend ones that I like. 

That being said, I realized that the specialized world which we operate in embraces some different ideas, unusual aesthetics, and is fascinated by the function of the environments we strive to replicate. These are important distinctions between what we are doing in substrates at Tannin, and the rest of the aquarium hobby is doing.

Our NatureBase line is not intended to supersede or replace the more commonly available products out there as your "standard" aquarium substrate  because: a) they're more expensive, b) they're not specifically "aesthetic enhancements", c) they are not intended to be planted aquarium substrates d) because of their composition, they'll add some turbidity and tint to the aquarium water, at least initially (not everyone could handle THAT!)

So, right there, those factors have significantly segmented our target market...I mean, we're not trying to be the aquarium world's "standard substrate", we're not marketing them just for the cool looks, and we can't emphasize enough that they will make your water a bit turbid when first submerged. Those factors alone will take us out of contention for large segments of the market.

This is important. I mean, these are intended to be used in more natural, botanical-style/biotope-inspired aquariums. They do exactly what I wanted them to do, and some of them are specifically intended for use in specialized set ups, like the "Urban Igapo" idea we've been talking about for a long time here, brackish water mangrove environments, etc.

Let's touch on the "aesthetic" part for a minute.

Most of our NatureBase substrates have a significant percentage of clays and sediments in their formulations. These materials have typically been something that aquarists have avoided, because they will cloud the water for a while, and often impart a bit of color. We also have some botanical components in a few of our substrates, because they are intended to be "terrestrial" substrates for a while before being flooded...and when this stuff is first wet, some of it will float. And that means that you're going to have to net it out, or let your filter take it out. You simply won't have that "issue" with your typical bag of aquarium sand!

Why sediments and clays? 

Well, for one thing, sediments are an integral part of the natural substrates in the habitats from which our fishes come. So, theyre integral to our line. In fact, I suppose you'd best classify NatureBase products as "sedimented substrates."

Many of our favorite habitats are forest floors which undergo periodic flooding cycles in the Amazon, which results in the creation of aquatic habitats for a remarkable diversity of fish species.

Depending on the type of water that flows from the surrounding rivers, the characteristics of the flooded areas may vary. another important impact is the geology of the substrates over which the rivers pass. This results in differences in the physical-chemical properties of the water. In the Amazon, areas flooded by rivers of black or clear waters, with acid pH and low sediment load in addition to being nutritionally poor, are called “igapó."

The flooding often lasts for several weeks or even several months, and the plants and trees need special biochemical adaptations to be able to survive the lack of oxygen around their roots. During the inundation period, many of the forest trees drop their fruits into the water, where they are eaten by fish. As an interesting side note, ecologists have noted that some of these trees and plants are strongly dependent on the fishes to disperse their seeds through the forest, requiring that the seeds pass through the gut of a fish before it will germinate. 


Forest floor soils in tropical areas are known by soil geologists as "oxisols", and have varying amounts of clay, sediments, minerals like quartz and silica, and various types of organic matter. So it makes sense that when flooded, these "ingredients" will have significant impact on the aquatic environment. This "recipe" is not only compositionally different than typical "off-the-shelf" aquarium sands and substrates- it looks and functions differently, too.

And that's where a lot of people will metaphorically "leave the room."

So, yeah, you'll have to make a mental shift to appreciate a different look and function. And many hobbyists simply can't handle that.

The igapo and varzea substrates are intended to be "terrestrial" for a period of time, to get the grasses and plants going, and then inundated. Same goes for simulations the Pantanal habitat...You CAN fill them with water right off the bat; however, you should be ready for some cloudy water for a week or more!

This is not unlike what occurs in the wild habitats...newly inundated forest floors have a lot of leaf litter, seed pods, etc., and will be quite turbid for some time. If you understand the context for which they are intended, and the habitats which they help to replicate, this is perfectly acceptable and logical...Of course, you need to make that "mental shift, right?"

Although these substrates can grow both terrestrial and aquatic plants well, they were not intended to be generic planted tank substrate. We're not trying to compete with the many fantastic specialized planted aquarium substrates out there. Rather, these are modeled after relatively nutrient-poor soils, which will grow plants, but not as well as the fancy clay pellets and such that are intended to grow plants.

Yeah, our Igapo and Varzea mixes can grow plants like grasses and marginals pretty well. You're just not going to be doing your next "Dutch-style" aquascape or "Iwagumi" with our products.

Our Igapo and Varzea substrates mimic sandy acidic soils that have a low nutrient content. And, as you know, the color and acidity of the floodwater is due to the acidic organic humic substances (tannins) that dissolve into it. The acidity from the water translates into acidic soils, which makes sense, right?

Now, I admit, I am NOT a geologist, and I"m not expert in soil science. I know enough to realize that, in order to replicate the types of habitats I am fascinated with require different materials. If you ask me "Will this fish do well with this materials?". or "Can I grow "Cryptocoryne in this?", or "Does this make a good substrate for shrimp tanks" I'll be the first to tell you that, while I have experimented with many species of plants, averts, and fishes with these substrates, I can't tell you that every single fish will like them. I'd be full of shit at best, and a liar at the worst- neither which I'd want!

Rather, I can tell you that these are some of the most unusual materials I've seen for  specialized aquariums, and that they are wide open for experimentation in various kinds of systems! And that's part of the key: These substrates, even though they've been used by myself, my staff, and some close friends for a while now, are really "experimental" in nature. Because you can do all sorts of cool stuff with them. Hell, you can even mix them with commercial, off-the-shelf substrates to make cool, functionally aesthetic "custom" mixes of your own!

We want you to use leaves, botanicals, and other materials with these unique substrates. They're intended to help foster the growth of beneficial bacteria, biofilms, fungal growth, and micro crustaceans, to help build up a functional, diverse benthic habitat in botanical-style aquariums. They will help form the literal "base" of your botanical-style aquarium system (hence the name of the product line, "NatureBase").

Even though I have a near-obsessive love for the flooded forest substrates, I'm equally as excited to share NatureBase "Mangal" with you- it's our specialized brackish-water mangrove habitat substrate- one that represents the culmination of a 4-year journey of researching, sourcing, mixing, and testing! As far as we know, three has not been a dedicated brackish water substrate offered before in the hobby, and we think it's yet another element for our "Estuary" line that will help revitalize and elevate this unique and oft-neglected hobby sector!


Regardless of how you use these new substrates, we hope that you understand the "why" part as much as the aesthetics that they bring.

And yeah, they are rather pricy, as compared to a typical bag of aquarium sand. I'd compare their pricing to the more "high-end" aquatic plant speciality substrates. These are literally hand-mixed substrates, with the components sourced from suppliers throughout he world. These aren't some mass-produced, re-purposed construction material or something. Rather, they are well-thought-out, carefully compounded natural materials, mixed expressly for the purpose of using in botanical-style aquariums. We went through a lot of iterations before arriving at our final versions!

We use them extensively in our own tanks. We love the results that we're getting...

And we hope that you will, too!

We'll have much, much more to say about these cool substrates as we get closer to launching them, so stay tuned for more!

Stay creative. Stay studious. Stay curious. Stay adventurous...

And Stay Wet.


Scott Fellman

Tannin Aquatics 





June 19, 2020


The "self-feeding aquarium?" A grand experiment, or a form of benign neglect?

Like most of you, I'm a borderline obsessive aquarist...

Like, I constantly observe, test, or tweak each and every tank, every day. That being said, I have learned over the years that a well thought-out aquarium doesn't need endless doting attention on a non-stop basis.

In fact, because of a busy travel schedule, "company building", and just life in general over the last few years, I even might have missed a water exchange or feeding or two..or three...or...

Yeah, I'm not proud of it- but I won't deny it, either.

In my world, missing water exchanges and feedings and such were, for many years, a sort of "scarlet letter" that you ended up wearing for all to see (well, even if no one else knew...you just felt, I dunno...guilty!).

Now, curiously, I always seemed to havereefing friends who were obsessed with- even proud of- their "ability" to run a "successful" system without water exchanges and such. Maybe rebellious types are somehow attracted to me or something? They'd actually use a sort of "reverse mentality", in which you'd hear them proudly brag about stuff like, "I never run a protein skimmer on my reef." Or, "I haven't done a water change in like a year!"  I mean, that was stuff that would make my head explode... I was like, "If you're gonna be a loser aquarist- don't brag about it!"

I take a dim view of some stuff (shocker, I know...)!

Successful tanks require effort and care.

Yeah, I was/am all about continuous, regular maintenance and dedicated husbandry practices-particularly water exchanges, for which there is simply no substitute for, or no valid reason NOT to execute, IMHO. However, there is one "basic" aspect of aquarium keeping that I have always employed a bit of an "intentional avoidance" of:


"WTF, Fellman. Skip a goddam water change...But feeding? Really?"

Yes. Really.

But before you totally trash me for being hypocritical or even lazy, attempting to brazenly flaunt convention, or simply being guilty of a form of "benign neglect"- hear me out. It's not really about being lazy. It's an intentional thing. I plan for it. In fact, you do too, even though you may not think about it.

And it might be a "sort of" deliberate attempt to flaunt convention...in a nice way, of course.

However, this "practice" is part of a larger thesis which I have about botanical-style aquariums and their management, operation, and benefits:

Of all of the things we do in our blackwater/botanical-style aquariums, one of the few "basic practices" that I think we can actually allow Nature to do some of the work on is to provide some sustenance for our fishes.

Think about it: We load up our systems with large quantities of leaves and botanicals, which serve as direct food for some species, such as shrimp, and perhaps Barbs and Loaches.

These materials famously recruit biofilm and fungal growths, which we have discussed ad nasueum here over the years. These are nutritious, natural food sources for most fishes and invertebrates. And of course, there are the associated microorganisms which feed on the decomposing botanicals and leaves and their resulting detritus.

Having some decomposing leaves, botanicals, and detritus helps foster supplemental food sources. 

Now, we have briefly talked about how decomposing leaf litter does support population of "infusoria"- a collective term used to describe minute aquatic creatures such as ciliates, euglenoids, protozoa, unicellular algae and small invertebrates that exist in freshwater ecosystems.

Yet, there is much to explore on this topic. It's no secret, or surprise- to most aquarists who've played with botanicals, that a tank with a healthy leaf litter component is a pretty good place for the rearing of fry of species associated with blackwater environments!

It's been observed by many aquarists, particularly those who breed loricariids, that the fry have significantly higher survival rates when reared in systems with leaves present. This is significant...I'm sure some success from this could be attributed to the population of infusoria, etc. present within the system as the leaves break down.

Biofilms, as we've discussed many times before, contain a complex mix of sugars, bacteria, and other materials, all of which are relatively nutritious for animals which feed on them.

It therefore would make a lot of sense that a botanical-influenced aquarium with a respectable growth of biofilm would be a great place to rear fry! Maybe not the most attractive place, from an aesthetic standpoint- but a system where the little guys are essentially "knee deep" in supplemental natural food at any given time is a beautiful thing to the busy fish breeder!

And yeah, my experience indicates it performs a similar role for adults fishes.

In the wild, creatures like hydracarines (mites), insects, like chironomids (hello, blood worms!), and copepods, like Daphnia, are the dominant fauna that fishes tend to feed on in these waters.  There's a lot of cool information that you can uncover when you deep dive into scientific information on our fishes- particularly gut content analysis of wild fishes.

Gut content analysis of fishes which inhabit leaf litter habitats reveals a lot of interesting things about what our fishes consume.

In addition to the above-referenced organisms, organic detritus and "undefined plant materials" are not uncommon in the diets of all sorts of fishes. This is interesting to contemplate when we consider what to feed our fishes in aquariums, isn't it?

It is. 

Anyways, these life forms, both planktonic and insect, tend to feed off of the leaf litter itself, as well as fungi and bacteria present in them as they decompose. The leaf litter bed is a surprisingly dynamic, and one might even say "rich" little benthic biotope, contained within the otherwise "impoverished" waters. I find this not only fascinating- but a fact that we as aquarists can embrace to create aquariums capable of supplementing- or even sustaining-our fishes via the nutrition they can provide.

And, as we've discussed before on these pages, it should come as no surprise that a large and surprisingly diverse assemblage of fishes make their homes within and closely adjacent to, these litter beds. These are little "food oases" in areas otherwise relatively devoid of food. The fishes are not there just to look at the pretty leaves!

They're there to feed and take advantage of the abundant and easy-to-access food resources.

And of course, it goes without saying that Nature works (if allowed to do so) in a similar manner in the aquarium!

The leaves and botanicals we add to our tanks do what they've done in Nature for eons: They support the basis for a surprisingly rich and diverse "food web", which enables many of the resident life forms- from bacteria, to insects...right up to our fishes- to derive some, if not all of their sustenance from this milieu.

Confession time?


I've created botanical tanks for years with part of the intention being to see if I can support the resident fishes with minimal external food inputs.

That felt better.

My rationale was that, not only will the leaves and botanicals help foster or sustain such "food webs" as they do in Nature, but that the lower amount of external food inputs by the aquarist helps foster a cleaner system, which is especially important when one takes into account the large amount of bioload decomposing leaves and botanicals account for in the aquarium!

And guess what? It works.

Just fine.

I've done this about 8 times in the past two years, with great results.

A beautiful case in point is one of my recent little office aquariums; a "nano" tank which was "scaped" only with  Texas Live Oak Leaf Litter,  Yellow Mangrove Leaves, and Oak Twigs.  (I know, we're currently awaiting a re-supply of Mangrove leaves any day now!)

Now I know that this tank isn't everyone's idea of aesthetic perfection..I mean, it's essentially a pile of  fucking leaves...However, to the fishes and other life forms which reside in the tank, it's their world; their food source.

And it's reminiscent of the wild habitats from which they come.

In that tank, I maintained a shoal of 25 "Green Neon Tetras", Parachierdon simulans, in this tank. This tank was  up and ran about 8 months without a single external food input since the fish were added to the tank.  They were subsisting entirely on the epiphytic matter and microorganisms found in the leaves...Nothing else.

And they were as active, fat, and happy as any Green Neons I've ever seen.

In fact, they more than doubled in size since I first obtained them. Some of the fishes were shockingly emaciated and weak upon arrival, were rehabilitated somewhat in quarantine, but weren't "100%" when released into the display (yeah, I know- NOT a "best practice", but it was intentional for this experiment).

After a few weeks, this point, I couldn't tell them apart from the rest of their tankmates!

Oh, and they spawned twice!

Perhaps just luck...but weakened, malnourished fishes generally don't reproduce in our aquariums, so I think that something good was going on there!

Now sure, this was a relatively small population of little fishes in a small tank. The environment itself was carefully monitored. Regular water exchanges and testing were employed.

All of the "usual stuff" we do in an aquarium...except feeding.

Of course, I don't think that such a success could be replicated with fishes like cichlids or other larger, more predatory type fishes, like Knife Fishes- unless you utilized a large aquarium with a significant "pre-stocked" population of crustaceans, insects, and maybe even (gulp) "feeder-type" fishes.

I mean, I suppose that you could do this...

However, it is really a more successful approach with fishes like characins, Rasbora, Danios, some catfishes, Loaches, etc.-Especially the little guys.

So yeah, I believe that this concept is entirely replicable, and can be successful with many fishes.It's not some "miracle", or an excise in "giving hobby convention the middle finger"- it's simply a way to set the stage for an aquarium to provide for its inhabitants' nutritional needs.

By stocking your new aquarium with a healthy allotment of leaves and botanicals, perhaps "seeding" it with beneficial bacteria, worms, micro crustaceans, Paramcium, etc., and letting the tank "run in" for a few weeks prior to adding your fishes, you're doing just that.

That's the hardest part of this whole idea. Letting Nature do some of the work.

It requires patience, observation, and some planning. Yet, it's entirely possible snd not hard to execute. It may require creating tanks which embrace a completely different aesthetic AND function. Stuff like detritus, turbidity, decomposition, and biofilms will be things that you find not only interesting, but helpful and desirable, too.

To some extent, it's certainly a bit "contrarian" as compared to standard aquarium practice, I suppose. However, it's not all that "radical" a concept, right? I mean, it's essentially allowing Nature to do what she does best- cultivate an ecosystem...which she will do, if given the "impetus" and left to her own devices. 

And it's not really "benign neglect", is it?

It's the facilitating of a process which has been going on in Nature for eons...a validation of what we experiment with on a daily basis in our "tinted" world. It's that "functionally aesthetic" thing again, right?

I think that, as we evolve into the next "era" of botanical-style aquarium practice, we'll see more and more interesting collateral benefits and analogs to the functions of natural aquatic ecosystems. We need to explore these characteristics and benefits as we develop our next generation of aquariums.

We invite you to experiment for yourself with this fascinating and compelling topic!

Stay inspired. Stay thoughtful. Stay curious. Stay patient. Stay skeptical. Stay observant..

And Stay Wet.


Scott Fellman

Tannin Aquatics 

June 18, 2020


Considering the seasons...

The botanical-style aquarium challenges us. 

It forces us to look at things a bit differently. To accept a different look, a different function, and to embrace Nature in a more intimate way in our aquariums that we typically do.

And, in order to make sense of it all, we spend a great deal of time examining the processes which occur when leaves and other botanicals are added to the aquarium.

And this is important, not only from an aesthetic standpoint, but from a functional/operational standpoint.

It definitely differs from our hobby practice in decades past, where the idea of throwing in materials that affect the water quality/composition was strictly a practice reserved for speciality hobbyists, like killifish breeders, Dwarf Cichlid keepers, etc., who wanted to create special conditions for breeding.

Nowadays, we're advocating the addition of such materials to our aquariums as a matter of course, for the everyday purpose of replicating natural processes for our fishes. We understand- or are attempting to understand- the impact on both our aquariums' ecology and the husbandry involved.

Yeah, sort of a different approach.

We add a lot of biological material to our tanks in the form of leaves and botanicals- perfectly analogous to the process of allochonous inputmaterial is something imported into an ecosystem from outside of it. Exactly what happens in the tropical streams and rivers that some of us obsess over!

There's been a fair amount of research and speculation by both scientists and hobbyists about the processes which occur when terrestrial materials like leaves and botanical items enter aquatic environments, and most of it is based upon field observations.

As hobbyists, we have a unique opportunity to observe firsthand the impact and affects of this material in our own aquariums! I love this aspect of our "practice", as it creates really interesting possibilities to embrace and create more naturally-functioning systems, while possibly even "validating" the field work done by scientists!

And of course, there are a lot of interesting bits of information that we can interpret from Nature when planning, creating, and operating our aquariums.

It goes without saying that there are implications for both the biology and chemistry of the aquatic habitats when leaves and other botanical materials enter them. Many of these are things that we as hobbyists observe every day in our aquariums!


A lab study I came upon found out that, when leaves are saturated in water, biofilm is at it's peak when other nutrients (i.e.; nitrate, phosphate, etc.) tested at their lowest limits. This is interesting to me, because it seems that, in our botanical-style, blackwater aquariums, biofilms tend to occur early on, when one would assume that these compounds are at their highest concentrations, right? And biofilms are essentially the byproduct of bacterial colonization, meaning that there must be a lot of "food" for the bacteria at some point if there is a lot of biofilm, right?

More questions...

Does this imply that the biofilms arrive on the scene and peak out really quickly; an indication that there is actually less nutrient in the water? Is the nutrient bound up in the biofilms? And when our fishes and other animals consume them, does this provide a significant source of sustenance for them?


Oh, and here is another interesting observation:

When leaves fall into streams, field studies have shown that their nitrogen content typically will increase. Why is this important? Scientists see this as evidence of microbial colonization, which is correlated by a measured increase in oxygen consumption. This is interesting to me, because the rare "disasters" that we see in our tanks (when we do see them, of course, which fortunately isn't very often at all)- are usually caused by the hobbyist adding a really large quantity of leaves at once, resulting in the fishes gasping at the surface- a sign of...oxygen depletion?

Makes sense, right? 

These are interesting clues about the process of decomposition of leaves when they enter into our aquatic ecosystems. They have implications for our use of botanicals and the way we manage our aquariums. I think that the simple fact that pH and oxygen tend to go down quickly when leaves are  initially submerged in pure water during lab tests gives us an idea as to what to expect.

A lot of the initial environmental changes will happen rather rapidly, and then stabilize over time. Which of course, leads me to conclude that the development of sufficient populations of organisms to process the incoming botanical load is a critical part of the establishment of our botanical-style aquariums.

Fungal populations are as important in the process of breaking down leaves and botanical materials in water as are higher organisms, like insects and crustaceans, which function as "shredders." So the “shredders” – the animals which feed upon the materials that fall into the streams, process this stuff into what scientists call “fine particulate organic matter.”

And that's where fungi and other microorganisms  make use of the leaves and materials, processing them into fine sediments. Allochthonous material can also include dissolved organic matter (DOM) carried into streams and re-distributed by water movement.

And the process happens surprisingly quickly.

In experiments carried out in tropical  rainforests in Venezuela, decomposition rates were really fast, with 50% of leaf mass lost in less than 10 days! Interesting, but is it tremendously surprising to us as botanical-style aquarium enthusiasts? I mean, we see leaves begin to soften and break down in a matter of a couple of weeks- with complete breakdown happening typically in a month or so for many leaves. And biofilms, fungi, and algae are still found in our aquariums in significant quantities throughout the process.

So, what's this all mean? What are the implications for aquariums? 

I think it means that we need to continue to foster the biological diversity of animals in our aquariums- embracing life at all levels- from bacteria to fungi to crustaceans to worms, and ultimately, our fishes...All forming the basis of a closed ecosystem, and perhaps a "food web" of sorts for our little aquatic microcosms. It's a very interesting  concept- a fascinating field for research for aquarists, and we all have the opportunity to participate in this on a most intimate level by simply observing what's happening in our aquariums every day!

Diversity is interesting enough, but when you factor in seasonal changes and cycles, it becomes an almost "foundational" component for a new way of running our botanical-style aquariums.

Consider this:

The wet season in The Amazon runs from November to June. And it rains almost every day.

And what's really interesting is that the surrounding Amazon rain forest is estimated by some scientists to create as much as 50% of its own precipitation! It does this via the humidity present in the forest itself, from the water vapor present on plant leaves- which contributes to the formation of rain clouds.

Yeah, trees in the Amazon release enough moisture through photosynthesis to create low-level clouds and literally generate rain, according to a recent study published in the Proceedings of the National Academy of Sciences (U.S.)!

That's crazy.

But it makes a lot of sense, right?

Okay, that's a cool "cocktail party sound bite" and all, but what happens to the (aquatic) environment in which our fishes live in when it rains?

Well, for one thing, rain performs the dual function of diluting organics, while transporting more nutrient and materials across the ecosystem. What happens in many of the regions of Amazonia - and likewise, in many tropical locales worldwide-is the evolution of our most compelling environmental niches...

The water levels in the rivers rise significantly- often several meters, and the once dry forest floor fills with water from the torrential rain and overflowing rivers and streams. In Amazonia, it means one thing:

The Igapos are formed. 

All of the botanical material- fallen leaves, branches, seed pods, and such, is suddenly submerged. And of course, currents re-distribute this material into little pockets and "stands", affecting the (now underwater) "topography" of the landscape. Leaves begin to accumulate. Tree branches tumble along the substrate  Soils dissolve their chemical constituents, tannins, and humic acids into the water, enriching it. Fungi and micororganisms begin to multiply, feed on and break down the materials. Biofilms form, crustaceans reproduce rapidly.  Fishes are able to find new food sources; new hiding places..new areas to spawn.

Life flourishes.

So, yeah, the rains have a huge impact on tropical aquatic ecosystems. And it's important to think of the relationship between the terrestrial habitat and the aquatic one when visualizing the possibilities of replicating nature in your aquarium in this context.

This is huge, important stuff that any real "natural aquascaping" enthusiast needs to get his/her head around. 

It's an intimate, interrelated, and perhaps even "codependent" sort of arrangement!

And of course, I think we can work with this stuff to our fishes' advantage!

We've talked about the idea of "flooding" a vivarium-type setup designed to replicate an Amazonian forest before. You know, sort of attempting to simulate some of the processes which happen seasonally in Nature. With the technology, materials, and information available to us today, the capability of creating a true "year-round" habitat simulation in the confines of an aquarium/vivarium setup has never been more attainable.

The time to play with this concept is now!

Sure, you'd need to create a technical means or set of procedures to gradually flood your "rainforest floor" in your tank, which could be accomplished manually, by simply pouring water into the vivarium over a series of days; or automatically, with solenoids controlling valves from a reservoir beneath the setup, or perhaps employing the "rain heads" that frog and herp people use in their systems. This is all very achievable, even for hobbyists like me with limited "DIY" skills.

You just have to innovate, and be willing to do a little work and experimentation.

And, you have to accept some new and very different aesthetics. You have to understand that when you flood a soil/clay/sediment-based substrate with water, it's going to be turbid. It's going to not be crystal clear and "aquarium culture perfect" in appearance.

When you make the mental shifts, you can just ponder the possibilities here! It's crazy!

As the display "floods", the materials in the formerly "terrestrial" environment become submerged- just like in Nature- releasing nutrients, humic substances, and tannins, creating a rich, dynamic habitat for fishes, offering many of the same benefits as you'd expect from the wild environment.

Recreating a "365 dynamic" environment in an aquatic feature would perhaps be the ultimate expression of an operational biotope-inspired aquarium- Truly mimicking the composition, aesthetics- and function of the natural habitat. A truly realistic representation of the wild, on a level previously not possible.

No more of that "diorama" bullshit.

Of course, I have no illusions about this being a rather labor-intensive process, fraught with a few technical challenges- but it's not necessary to make it complicated or difficult.

You'll have to be patient and make smaller, slower, incremental moves...I mean, you're starting out with a "dry" aquarium- a representation of a forest floor or grassland, letting it thrive- and then flooding it.

It does require some "active management", planning, and diligence- but on the surface, executing seems no more difficult than with some of the other aquatic systems we dabble with, right?

The transformation of dry forest floors into aquatic habitats provides a tremendous amount if inspiration AND biological diversity and activity for both the natural environment and our aquariums.

As always, it's best to look to Nature for your inspiration. You simply won't find much in the way of aquariums created to replicate these habitats and processes just yet.

And, man- Nature provides some really incredible inspiration for this stuff, doesn't it?

Flood pulses in these habitats easily enable large-scale "transfers" of nutrients and food items between the terrestrial and aquatic environment. This is of huge importance to the ecosystem. As we've touched on before, aquatic food webs in the Amazon area (and in other tropical ecosystems) are very strongly influenced by the input of terrestrial materials, and this is really an important point for those of us interested in creating more natural aquatic displays and microcosms for the fishes we wish to keep.

Characins, catfishes, dwarf cichlids, annual killifish- all have unique relationships with these habitats, which we can replicate, study, and interpret. They respond to the seasonal changes almost predictably.

And the seasonality in these wild aquatic habitats is perhaps the one feature that we as aquarists have yet to fully embrace and study. It's fascinating, intriguing...and dramatic, in many cases!

What can we learn from these seasonal inundations?

Well, for one thing, we can observe the diets of our fishes.

In general, fish, detritus and insects form the most important food resources supporting the fish communities in both wet and dry seasons, but the proportions of invertebrates fruits, and fish are reduced during the low water season. Individual fish species exhibit diet changes between high water and low water seasons in these areas...an interesting adaptation and possible application for hobbyists?

Well, think about the results from one study of gut-content analysis form some herbivorous Amazonian fishes in both the wet and dry seasons: The consumption of fruits in Mylossoma and Colossoma species was significantly less during the low water periods, and  their diet was changed, with these materials substituted by plant parts and invertebrates, which were more abundant.

Fruit-eating is significantly reduced during the low water period when the fruit sources in the forests are not readily accessible to the fish. During these periods of time, fruit eating fishes ("frugivores") consume more seeds than fruits, and supplement their diets with foods like as leaves, detritus, and plankton. Interestingly, even the known "gazers", like Leporinus,  were found to consume a greater proportion of materials like seeds during the low water season.

Mud and algal growth on plants, rocks, submerged trees, etc. is quite abundant in these waters at various times of the year. Mud and detritus are transported via the overflowing rivers into flooded areas, and contribute to the forest leaf litter and other botanical materials, coming nutrient sources which contribute to the growth of this epiphytic algae. 

During the lower water periods, this "organic layer" helps compensate for the shortage of other food sources. When the water is at a high period and the forests are inundated, many terrestrial insects fall into the water and are consumed by fishes. In general, insects- both terrestrial and aquatic, support a large community of fishes.

So, it goes without saying that the importance of insects and fruits- which are essentially derived from the flooded forests, are reduced during the dry season when fishes are confined to open water and feed on different materials. 

So I wonder...is part of the key to successfully conditioning and breeding some of the fishes found in these habitats altering their diets to mimic the seasonal importance/scarcity of various food items? In other words, feeding more insects at one time of the year, and perhaps allowing fishes to graze on detritus and biocover at other times?

Is the concept of creating a seasonally-influenced,  "food-producing" aquarium, complete with detritus, natural mud, and an abundance of decomposing botanical materials, a key to creating a more true realistic feeding dynamic, as well as an "aesthetically functional" aquarium?

I'm fairly certain that this idea will make me even less popular with some in the so-called "Nature Aquarium" crowd, which, in my opinion, has sort of appropriated the descriptor while really embracing only one aspect of nature (i.e.; plants)...Hey, I love the look of many of those tanks as much as anyone...but let's face it, a truly "natural" aquarium needs to embrace stuff like detritus, mud, decomposing botanical materials, varying water tint and clarity, etc.

If you are intrigued by that, and not frightened of the looks and operational considerations, you'll love NatureBase "Igapo" substrate. After over a year of testing, it's now weeks away from release...It'll challenge you. It'll create turbidity. It'll color the water. It'll grow terrestrial grasses. It will foster biofilm formation. It'll get your creative juices flowing. 

And we think it will reinforce the idea of what we mean by "functional aesthetics."

The aesthetics might not be everyone's cup of tea, but the possibilities for creating more self-sustaining, ecologically sound microcosms are numerous, and the potential benefits for fishes are many. Creating aquariums based on specific natural functions and benefits is something that I can't resist.

And, since a few of you asked...THAT is where Tannin is headed in the second half of 2020 and into next year. A new approach. A different look, products that might have you scratching your head in sheer terror AND delight! We're going to do a lot more pushing out into the margins of what is considered "normal" in the hobby. 

And that's just where we like to be.

Stay excited. Stay focused. Stay inspired. Stay creative. Stay tuned...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


June 17, 2020


The impact of the land...the concept of terroir-and the nuances of Nature.

To me, perhaps one of the most elegant and compelling aspects of Nature is how the aquatic environments we love are so profoundly influenced by the terrestrial habitats which surround them. 

There is a remarkable similarity between this intimate land/water relationship, and the world that we can create in our aquariums.

Every aquarium that we assemble is not only a unique expression of our interests and skills- it's a complex, ecologically functional microcosm, which is impacted by not only the way we assemble the life forms, but how we utilize them.

And of course, being the self-appointed "World's most prolific aquarium hobby philosopher,"  I have spent a fair amount of time ruminating on the idea, attempting to grasp the concept.

I think it simply starts with the materials that we use in our aquairums.

It is perfectly logical to imply that botanicals, wood, and other materials which we ultiize in our aquascapes not only have an aesthetic impact, but a consequential physical-chemical impact on the overall aquatic environment, as well.

We know this, because we see their impact on natural aquatic systems all the time, don't we? Every flooded forest, inundated Terre Firme grassland, every overflowing stream- provides a perfect example for us to study.

The land influences the water.

Each component of the terrestrial habitat has some unique impact on the aquatic habitat. Not really difficult to grasp, when you think about it in the context of stuff we know and love in other areas of life.

Wine, for example, has "terroir"- the environmental conditions, especially soil and climate, in which grapes are grown and that give a wine its unique flavor and aroma...  Coffee also acquires traits that are similar:  Tangible effects and characteristics, which impact the experience we get from them.

And of course,  I can't help but wonder if this same idea applies to our botanicals?

It must!

Sure, it does.

I mean, leaves come from specific trees, imparting not only tannins and humic substances into the water, but likely falling in heavier concentrations, or accumulating in various parts of rain forest streams or inundated forest floors at particular times of the year, or in specific physical locales with in a stream or river. And of course, they provide the fishes which reside in that given area a specific set of physical/chemical conditions, which they have adapted to over time. 

Is this not the very definition of "terroir?"

Yeah, sort of...right? 

Actually, the idea makes perfect sense.

As we've discussed before, the soils, plants, and surrounding geography of an aquatic habitat play an important and intricate role in the composition of the aquatic environment. They influence not only the chemical characteristics of the water (like pH, TDS, alkalinity), but the color (yeah- tannins!), turbidity, and other characteristics, like the water flow. Large concentrations become physical structures in the course of a stream or river that affect the course of the water.

And of course, they also have important impact on the diet of fishes...Remember allochthonous input form the land surrounding aquatic habitats? And the impact of humic substances?

I can't help but wonder what sorts of specific environmental variations we can create in our aquarium habitats; that is to say, "variations" of the chemical composition of the water in our aquarium habitats- by employing various different types and combinations of botanicals and aquatic soils.

I mean, on the surface, this is not a revolutionary idea...We've been doing stuff like this in the hobby for a while- more crudely in the fish-breeding realm (adding peat to water, for example...), or with aragonite substrates in Africa Rift Lake cichlid tanks, or with mineral additions to shrimp habitats, etc.

In the planted aquarium world, it's long been known that soil types/additives, ie;  clay-based aquatic soils, for example, will obviously impact the water chemistry of the aquarium far differently than say, iron-based soils, and thusly, their effect on the plants, fishes, and, as a perhaps unintended) side consequence, the overall aquatic environment will differ significantly as a result.

So, it pretty much goes without saying that the idea that utilizing different types of botanical materials in the aquarium can likely yield different effects on the water chemistry, and thus impact the lives of the fishes and plants that reside there- is not that big of a "stretch", right? I can't help but wonder what the possible impacts of different leaves, or possibly even seed pods from different geographic areas can have on the water and overall aquarium environment.

I mean, sure, pH and such are affected in certain circumstances - but what about the compounds and substances we don't- or simply can't- test for in the aquarium? What impacts do they have? Subtle things, like combinations of various amino acids, antioxidant compounds, obscure trace elements- even hormones, for that matter...Could utilizing different combinations of botanicals in aquariums potentially yield different results? You know- scenarios like,  "Add this if you want fishes to color up. Add a combination of THIS if you want the fishes to commence spawning behavior", etc.

It sounds a bit exotic, a bit gimmicky, even, but is it really all that far-fetched an idea?

Absolutely not, IMHO.

I think the main thing which keeps the idea from really developing more in the hobby- knowing exactly how much of what to add to our tanks, specifically to achieve "x" effect- is that we as hobbyists simply don't have the means to test for many of the compounds which may affect the aquarium habitat.

At this point, it's really as much of an "art" as it is a "science", and more superficial observation- at least in our aquariums- is probably almost ("almost...") as useful as laboratory testing is in the wild. Even simply observing the effects upon our fishes caused by environmental changes, etc. is useful to some extent.

At least at the present time, we're largely limited to making these sort of "superficial" observations about stuff like the color a specific botanical can impart into the water, etc. It's a good start. 

Of course, not everything we can gain from this is superficial...some botanical materials actually do have scientifically confirmed impacts on the aquarium environment.

In the case of catappa leaves, for example, we can at least infer that there are some substances (flavonoids, like kaempferol and quercetin, a number of tannins, like punicalin and punicalagin, as well as a suite of saponins and phytosterols) imparted into the water from the leaves- which do have scientifically documented affects on fish health and vitality. 

When we first started Tannin, I came up with the term "habitat enrichment" to describe the way various botanicals can impact the aquarium environment. I mused on the idea a lot. (I know that doesn't surprise many of you, lol...)

Now, I freely admit that this term may be interpreted as much more of a form of "marketing hyperbole" as it is a useful description. However, I believe that the idea sort of resonates, when we think of the aquarium as an analog for the wild aquatic habitats, and how the surrounding environment- the terroir- impacts the aquatic environment, right?

And we hear the interesting stories from fellow hobbyists about dramatic color changes, positive behavioral changes,  rehabilitated fishes, and those "spontaneous" spawning events, which seem to occur after a few weeks of utilizing various botanicals in aquariums which formerly did not employ them.

Sure, a good number of these interesting events and effects could likely be written off as mere "coincidences"- but when it happens over and over and over again in this context, I think it at least warrants some consideration! 

We're slowly beginning to figure this stuff out.

Yeah, we’re artists.

Mad scientists.

Fish geeks.


Yeah, artists.

And this stuff is really as much of an “art” as it is a “science”, IMHO.

There is so much we don’t know yet. Or, more specifically, so much we don’t know in the context of keeping fishes. We need to tie a few loose ends together to get a really good read on this stuff…until we get to the "Dial-a-River” additive stage ("Just add a little of this and a bit of that, and...".)

But we're getting there...At least in terms of understanding some of the tangible benefits of botanical use, besides just the aesthetics.

And it all starts with understanding the impact of...the terroir, right?

I think so.

I think that really sums up how much amazing stuff there is to extrapolate from observing the nuances of Nature.

Stay resourceful. Stay observant. Stay curious. Stay resourceful. Stay open-minded...

And Stay Wet.


Scott Fellman

Tannin Aquatics 




June 16, 2020


Don't even think about it...

I have some strong words and opinions about stuff I the aquarium world. And I am not afraid to share them with you on many days.

Today is one of those days. I needed to clarify, explain, and share some ideas.

Someone asked me the other day, rather innocently, I might add- how we "invented the idea of using botanicals in the aquarium." And, as I often do, after I cringed, I strongly and immediately corrected her, and explained that there is no single hobbyist or vendor who "invented" the idea. As long as people have been playing with aquariums, they've been throwing twigs and leaves and such into them- for various reasons and with various goals.

Nevertheless, it's not some "new practice" that Tannin Aquatics "invented."

I don't know why we as hobbyists need to assign a "creator" or "inventor" to everything. It's a bit weird. Now, if you want to give us "credit" for something, you can consider this:

The term "botanicals" didn't even exist as a contextual descriptor for this stuff in aquariums until about, oh, say 2015...when started Tannin and used the term to describe them. I appropriated this term, because the hobby needed a good descriptor of what this stuff was- especially if- as was my goal- we intended to make the practice of using them to create specific environmental effects in our tanks  more "mainstream" in the hobby. I don't claim many things in the aquarium hobby, but I will claim this one. 

Developing terminology and process are important parts of elevating hobby practices.Yeah, I suppose I'm acting rather boorishly about this because hobby "history" is important to me, and I want to set the history straight, because the "botanical-style" aquarium is still evolving, and we need to understand the difference between a more disciplined approach, and simply tossing some seed pods and such into a tank (as hobbyists HAVE been doing for many years.).

I'll say it again- WE DID NOT INVENT THE IDEA. No one did. 

"Well, if you didn't "invent" the stuff, what the hell DID you do?" (as if it really even matters, BTW)

What we did do was to source, test, research, and refine the practices involved in utilizing botanical materials safely and more predictably in aquariums. And taking this stuff to a more serious level required not only the aforementioned work- it required some descriptors and definitions.

And of course, while we're on the subject of definitions: Botanicals are simply natural plant materials (generally leaves, bark, wood, and seed pods) that are used for both decorative and environmental enrichment purposes in our aquariums. "Scott, you sell twigs and nuts!" as one of my reef-keeping friends profoundly declared! I suppose he wasn't too far off, although I think that was a bit over-generalized, lol. 

Now, the interesting thing is that, as hobbyists often do, we had to fight off the most "superficial" aspects of the description of our practice. We had to overcome the perception that utilizing botanicals was just some form of "aquascaping." I mean, sure, there is a large and significant aesthetic component to what we do. However, the most important aspect of utilizing botanicals in the aquarium is that they have the ability to influence the closed environment of the aquarium in a number of ways.

Many fishes (particularly South American fishes like Tetras, Cichlids and catfishes), as well as numerous African and Southeast Asian species (Gouramis, Bettas, etc.) benefit from the tannic acids and humic substances released by these materials into the water.

It has long been understood that there are actually some antifungal and possibly even antibacterial benefits to the properties inherent to "blackwater", resulting in healthier fishes and more viable spawns. And of course, botanical materials can help us recreate, to some extent, these conditions in the aquarium. And of course, it's not just environmental benefits that we see: Some animals, such as Plecos and even ornamental shrimp, derive supplemental nutrition from grazing on these materials.

And there are the expectations of what happens when we put these botanical materials into aquariums. We HAVE to consider these things. Not only because they impact our fishes' lives- but because they require us as hobbyists to make mental shifts to accept the function and appearance of these aquariums. This is perhaps different than almost any other aquarium approach out there at the moment. This is what we've spent a decade prior to starting Tannin, and the five years since we commenced business helping to flesh out, define, and explain.

Do you want a perfectly predictable sequence of occurrences and expectations for your botanical-style aquarium? Don't waste your time...Don't even think about it. Perfect predictability is just not a "thing" with these tanks. That being said, over the decades, we have noticed a specific group of phenomenon that occur with some regularity in botanical-style aquariums. Our experience positions us perfectly to help disseminate this information.

And THAT is the crux of why we spend SO much time and space discussing this stuff. We want expectations and experiences to be realistic and appropriate. That's our contribution to this game.

One of the things that we all experience with these types of systems is an initial burst of  tannins, which likely will provide a significant amount of visible color to the water. If you're not using activated carbon or some other filtration media, this tint will be more pronounced and likely last longer than if you're actively removing it with these materials!

You might also experience a bit of initial "cloudiness" in your water. This could either be physical dust or other materials released from the tissues botanicals, or even a burst of bacteria/microorganisms. Not really sure, but it usually passes quickly with minimal, if any intervention on your part. Oh, and interestingly enough-  not everyone experiences this...often this is a phenomenon which seems to happen in brand new tanks...so it might not even be directly attributable to the presence of the botanicals (well, at least not 100%). It might be other materials. It could be the sand, or dust/dirt from the other hardscape materials or the tank itself.

Of course, for those of you who will experiment with our NatureBase "Varzea" and "Igapo" substrates when they debut, you WILL experience cloudiness, turbidity, and tint as just part of the game. You'll either love it or hate it. But you will experience it! How much of a mental shift can you make to accept this as "normal" for your aquarium? That's the big question.

If you can't, our recommendation is that you don't even THINK about purchasing these substrates. Just don't. 

As with so many things in our practice of botanical-style aquarium keeping, we need to turn to Nature for a "prototype" of how these habitats are SUPPOSED to look and function.

This is aquarium keeping at its most raw, elemental, and yeah- natural. In a strange way, it's actually "cutting edge"- and that means that the "expectation set" is new, different, and unlike anything we've been indoctrinated to accept in the hobby before. It will challenge you. Test you. Perhaps it'll even piss you off- because it's not "Nature Aquarium" sterile artistic beauty. It's hard for many hobbyists to accept. And that's understandable and okay. 

If this shit bothers you...just don't even think about setting up one of these types of tanks.


So, that being said...what happens next in a typical botanical-style aquarium as it evolves?

Well, typically, as most of you who've played with this stuff know, the botanicals will begin to soften and break down over a period of several weeks. As we've discussed ad nauseum, you have the option to leave 'em in as they break down, or remove them (whatever your aesthetic sensibilities tell you to do!). Many "Tinters" have been leaving their botanicals in until completely decomposed, utilizing them as almost some sort of botanical "mulch", particularly in planted aquariums, and have reported excellent results.

Sure, the stuff will go through that biofilm phase before ultimately breaking down, and you'll have many opportunities to remove it...or in the case of most hobbyists these days- enjoy it for the food and biodiversity it brings to your system. And you will likely add new materials as the old ones break down...completely analogous to  "leaf drop" which occurs in the wild aquatic habitats we seek to replicate.

I have never had any negative side effects that we could attribute to leaving botanicals to completely break down in an otherwise healthy aquarium. Many, many users (present company included) see no detectable increases in nitrate or phosphate as a result of this process. Of course, this has prompted me to postulate that perhaps they form a sort of natural biological filtration media and actually foster some dentritifcation, etc. I have no scientific evidence to back up this theory, of course (like most of my theories, lol), but I think there might be a grain of truth here!

We're going to introduce some products later in the Summer/Fall which will address the biological "operating system" of botanical-style aquariums in ways not previously done. Suffice it to say, they'll require not only mental shifts on your part, but some observation, experimentation, education, and dedication. Not into that? Don't even think about trying them. Really. It's okay.

Oh, speaking of expectations- one of the "givens" of botanical aquarium keeping is that you will likely have to clean/replace prefilters, micron socks, and filter pads more frequently. Just like in Nature, as the botanicals (leaves, in particular) begin to break down, you'll see some of the material suspended in the water column from time to time, and the bits and pieces which get pulled into your filter will definitely slow down the flow over time. Stuff breaks down, and you can't stop it. Well, not unless you're standing by with a siphon hose by your tank 24/7/365.

The best solution, IMHO, is to simply change prefilters frequently and clean pumps/powerheads regularly as part of your weekly maintenance regimen.


Not into that? Well, you know what I'm going to say...

And of course...this is the elegant segue into the part about your "weekly maintenance regimen", right?

Well, here's my simple thoughts on this: Do "whatever floats your boat", as they say. If you're a bi-weekly-type of tank maintenance person, do that. If you're a once-a-month kind of person...Well, you might want to re-examine that! LOL. Botanical-style blackwater tanks, although remarkably stable and easy-going once up and running, really aren't true "set-and-forget" systems, IMHO.

You want to at least take a weekly or bi-weekly assessment on their performance and overall condition. Now, far be it from me to tell YOU- the experienced aquarist-how to run your tanks. However, I'm just sort of giving you a broad-based recommendation based upon my experiences, and those of many others over the years with these types of systems. You need to decide what works best for you and your animals, of course...

Now, remember, you're dealing with a tank filled with decomposing botanical materials. I mean, what do you THINK is going to be "normal" for a tank like this? Good overall husbandry is necessary to keep your tank stable and healthy- and that includes the dreaded (by many, that is) regular water exchanges. As we pointed out, at the very least, you'll likely be cleaning and/or replacing pre filter media as part of your routine, and that's typically a weekly-to bi-weekly thing.  

Just sort of goes with the territory here. Because, ya' know- leaves.

Oh, and during water exchanges, I typically will siphon out any debris which have lodged where I don't want 'em (like on the leaves of that nice Amazon Sword Plant right up front, or whatever). However, for the most part, I'm merely siphoning water from down low in the water column.

I'm a sort of "leave 'em alone as they decompose" kind of guy. And I'm not going to go into all the nuances of water preparation, etc. You have your ways and they work for you. If you want to hear my way some time, just DM me on Facebook or Instagram or whatever and we can discuss. It's not really rocket science or anything, but everyone has their own techniques.

And of course, regular water testing is important.

So, your testing regimen should include things like pH, TDS, alkalinity, and if you're so inclined, nitrate and phosphate. Logging this information over time will give us all some good data upon which to develop our expectations and best practices for water quality management.

Not just for the information you'll gain about your own aquarium and it's trends. It's important because we as proponents of the botanical-style aquarium movement need to log and share information about our systems, so we can develop a model for baseline performance of these systems, and continue to develop and refine  "standards" for techniques, practices, and expectations about these tanks. You're a pioneer of sorts, regardless of if you perceive yourself to be one or not!

Don't like that aspect? Well, don't even think about setting up one of these tanks.


Ouch. I'm hitting hard this morning!

I am, because you need to understand that playing with botanical-style aquariums is more than just a "style" of aquascaping. It's not just about then look. In fact, the function- the very nature of what we do and want to achieve with these tanks is what dictates the "look." It's about process.

"Setting the stage" for the process to take its course is only the beginning. Then comes the part about letting goa bit. Allowing Nature to evolve our work. We can look on in awe, and take delight in what is happening. 

To find little vignettes- little moments- of fleeting beauty that need not be permanent to enjoy.

And the changes...those earthy, perhaps inevitable changes which occur when terrestrial materials are submerged in water for an extended period of time? They're elegant- yet untamed...and not everyone's idea of "beautiful." Why? Largely because we don't control every aspect of the process; because we don't impose excessive amounts of order or influence to it.

We cede some of it to Nature...And that includes accepting the "look" as well.

It's hard.

Really hard for many.

Some people just "don't get it", and proffer that this is simply sloppy, not thought-out, and seemingly random. I recall vividly one critic on a Facebook forum, who, observing a recent botanical-inspired aquascape created by another hobbyist, commented that the 'scape looked like "...someone just threw in some pods and leaves in a random fashion.." 

Yeah, this guy actually described the aesthetic to a certain (although unsophisticated) degree...but he couldn't get past the look, and therefore concluded it was, "...haphazard, sloppy, and not thought out."

A shame.

I think if he glanced at a natural habitat and then looked at the tank again, he'd gain a new appreciation. Or at least, a sort of understanding.

But on the other hand, that was the charm and beauty of such a conceptual work. The seemingly random, transient nature of such an aquascape, with leaves deposited as in Nature by currents, tidal flows, etc., settling in unlikely areas within the hardscape.

Allowing Her some of that control.

Not everyone likes this nor appreciates it. And that's perfectly fine. It's not the "best" way to run a tank. Just "a way."

With so many people worldwide starting to play seriously with blackwater, botanical-style tanks, we're seeing more and more common trends, questions, ideas, issues, and ways to manage them...a necessary evolution, and one which we can all contribute to! 

Yet, if you're not into this...If you think setting up one of these tanks is just gonna be a cool "look" for your fish room, requiring little effort. If you're just trying to jump on someone sort of "trend"...Please- I beg you...Don't even think about it.

Help evolve the hobby.

Stay bold. Stay strong. Stay observant. Stay thoughtful. Stay diligent. Stay open-minded. Stay adventurous...

And Stay Wet.


Scott Fellman

Tannin Aquatics 



June 15, 2020


"Any old log..."

Some of the most compelling things in natural aquatic habitats- and in the aquariums which we create to represent them- are large branches, fallen trees, and logs. The result of a tree, branch, or root system which finds its way into the water is a physical, environmental, and water-flow-dynamic-changing feature in the habitat.

I love fallen trees and branches.

I love what they can do. What they can bring to an aquatic environment.

I love how they inspire us.

I love the idea of doing an aquarium in which the primary feature is a big old piece of wood, covered in biofilm, algae, and other life forms.

Notice I didn't say "aquatic moss?" Why? Well, besides the fact that it's sort of an aquascaping contest cliche by now, I don't think it looks all that "authentic." Although I like the look of these features, personally, I have yet to see a moss-covered log in the Amazon region, or in an Asian blackwater swamp, and we need to accept- not fight- some of what really happens in Nature, and readjust our aesthetic sensibilities to understand what is really natural beauty.

It's not all neat and orderly and crisp green on brown.

It's just not. 

As we've mentioned numerous times here, Nature is not exactly a neat and tidy, perfectly-ratioed place. Rather it's often a world of chaos, randomness, detritus, biofilms, and fungal growth.

I think we have to sort of "desensitize" ourselves from the stigma of "biocover" on our wood. Now, I know, this idea undermines a century of aquarium-keeping/aquascaping dogma, which suggests that wood in the aquarium must be pristine, and without anything going on it (outside of the aforementioned mosses, in the last decade or so). 

And of course, that's really sort of antithetical to what happens in Nature!

When terrestrial materials fall into the water, opportunistic life forms, ranging from algae to fungi to bacteria- even sponges-will colonize the available space, eking out a living as they compete for resources. In addition to helping to break down some of these terrestrial materials, the life forms that inhabit submerged tree branches and such reproduce rapidly, providing forage for insects and aquatic crustaceans, which, in turn are preyed upon by fishes. Yeah, a food chain...started by a piece of tree that fell in the forested was covered by water during periods of inundation.

If you look at the way the "biocover" (such a generic term, wouldn't you say?) grows on these materials, it's obvious that it does so in a manner which helps it absorb light, dissolved oxygen, and nutrients from the water column. The largest, broadest surfaces are covered.

These mats of what many hobbyists would characterize as "unsightly growth" are some of Nature's most beautiful and elegant systems, optimized to exploit the dynamic environment in which they are situated. An enormous abundance of life is present, if we just take a few minutes to look for it. 

Now, as a hobbyist, I do get it.

We like things orderly. We like to see things looking "pristine" and well-kept...and I understand that well. For decades I was the guy who you wouldn't see a speck of algae in his tanks...Like, none. My reef tanks were so clean looking that one of my friends jokingly suggested that "you could give birth in there..."

But guess what? "sterile" is not natural.

At least, not in most aquatic habitats.

I see how planted tank people take great care to optimize the environment for the plants, eliminating any algae they can find, in favor of lush plant growth. And that makes sense in that context. However, when I see systems comprised of perfectly "ratio-obeying" rocks, covered in mosses, with neat "lawns" of low-cut, perfectly manicured grass on the substrate, the word "natural" doesn't immediately come to mind.

Rather, I find them stunningly beautiful, much in the same manner as a finely-kept garden or planter box. A piece of art. Respect the enormous effort and talent that went in to planning, executing, and maintaining the tank. I take exception with the moniker of "natural-looking" ascribed to many such tanks. Natural, perhaps in the sense that plants and aquatic life forms are growing there...but that's about it, IMHO.

Nature is simply not neat and orderly. Not in the "design" sense. Nature does not correspond to our need to index and arrange color, growth forms, leaf shapes in their proper place, according to some artificial ratios and rules.


Nature is based on a sort of chaos. Or, being able to take advantage of chaos, anyways.

It's based on living things fighting to survive in a world which is not forgiving of life forms that cannot adapt to their environment. And as such, it has a compelling, almost relaxing beauty all of its own.

This viewpoint and willingness to embrace this more functionally-aesthetic interpretation  of Nature does not make me popular with some people, especially some in the aquascaping community, who feel that we are pushing the idea of "lax maintenance", "low concept" design, and "shoddy execution" (all actual words used by self-appointed "critics" to describe blackwater, botanical-style aquariums at one time or another over the years!).

I hate conflict, and have nothing but respect for most of these talented people, yet it seems we always receive some serious "rancor" from a few parties regarding our aesthetic. And frankly, I would rather spend more time on "The Tint" executing and creating content on some cool new ideas, but there is a valuable- and timely lesson to be learned here.

It's about acceptance, tolerance, and understanding.

I would imagine that the initial appearance of a botanical-style, blackwater aquarium makes it an easy target for those who are dogmatic, narrow minded and haven't got a clue on how these systems operate.

And let's be honest, I've never worked with a customer who created a botanical-style blackwater tank aquascape by just "tossing stuff in at random" (although that would be cool!).  There IS a LOT of thought an planning involved I the execution of these systems. Remember, we're not strictly about aesthetics. We're about fostering natural function, and the aesthetics are just a part of the whole equation.

The aesthetics often become far more enhanced after the aquarium has operated a period of time, resulting in a look that is often a bit different than we might have originally expected!

Botanical-style systems are different. They allow Nature to do a fair amount of the work, unobstructed by our regular intervention. This frightens some people. Yet, it's the ultimate expression of the concept of wabi-sabi, which Takashi Amano admired so much and urged us to embrace for so long. IMHO, it's the most critical- and most disregarded lesson he ever taught. Please Google it.

Yeah, these systems force us to look at Nature as it is...not simply as we want it to look.

These systems are so contrary to the hyper-dogmatic, homogenized, rule-driven lane that many of these "critics" operate in, that they simply cannot comprehend why people create such aquariums! If it weren't indicative of a problem, it would be funny.

Plenty of thought, skill, and effort goes into creating one of blackwater, botanical-style aquariums. You people are damn good!

There is a reason why the idea of creating these types of aquariums is literally exploding worldwide. They offer huge opportunities to express creativity, and to learn and contribute to an important body of knowledge within this speciality. They aren't that much different than what are touted as "high concept" aquariums by some, requiring plenty of planning, understanding, and talent to create and manage.

The opportunity to look at a feature one sees in a natural habitat and recreate the look and function of it is more enticing than ever before, given this mental shift. We just need to look at these natural features, consider how and why they formed, and what advantages they offer the aquatic life forms which resides in the. A more "wholistic" approach, indeed.

And then, we simply need to execute, unencumbered by artificial "rules" imposed by hobby dogma. A huge mental shift.

It's what comes after the tank is set up that really starts to differ from more "conventional" aquascaping and aquarium management.

The acceptance of natural processes, regardless of their appearance is key.  Making the effort to understand what is happening in our tanks, why it happens, and how these processes, if left "unedited", are exactly what happen in the wild aquatic habitats of the world.

A common "criticism" I hear from some people is that botanical tanks, with their brown water, biofilms, and decaying leaves, are a "cover" for "lack of technique" or "poor maintenance." To which I often respond, "Leave your 'scape alone for three weeks without touching anything on it, and I'll do the same with mine...lets see how much our tanks change."

Of course, there are never any takers among these critics, because they know that their tanks will "devolve" into what they would call "chaos" if they're not tending to it constantly. Some plants will overgrow others. Some will die back. The perfectly organized planting groups will fall by the wayside as the more dominant plants exploit the available resources. The botanical-style aquarium, which functions in a very natural manner, simply...continues to evolve. Leaves and pods decompose, fungal or biofilm growths wax and wane. Occasional strands of algae might pop up on a branch somewhere. Plants grow in the direction of light and nutrients. Just like in Nature, perhaps?

Fighting back nature does not make a tank "natural", IMHO.

Accepting it does.

And that requires talent, knowledge, and understanding on the part of the hobbyist.

And, just like accepting Nature, the hobby also needs to accept the fact that not everyone buys into everyone else's concept of what looks good, what's "cool", and what constitutes "natural" or whatever. Ironically, the highly talented people who unfairly criticize this style of aquarium are possibly ones who could contribute the most towards evolving them!  

Why some people love to bash the efforts and interests of others is beyond me. No one "owns" the idea of aquascaping. There is no "right or wrong" here; criticisms of things we haven't even tried before are not helpful.

They frighten off some individuals from even trying new things; questioning new ideas. How is that helpful?  To what end is this necessary? Now, in all fairness, it's a very small percentage of people who level such criticisms, but they are so vocal and venomous in their assertions that to not consider what they're saying and respond to them would be irresponsible on my part. We have received so much positive input, enthusiasm, and encouragement (not to mention, some awesome aquascapes!) from some of the world's most highly regarded aquascapers, that it's almost funny to hear such negativity...but, "people are people", right?

Guess the eternal optimist in me keeps thinking I can reach some of these people...not trying to convince them to create a blackwater/botanical aquarium; rather, to get them to simply understand that there is more than one methodology that can be used to create an amazing aquarium. To look to Nature not as just a "muse"- but as a teacher.

It's not that difficult a concept.

Enough divisiveness already! We're all aquarium hobbyists.

And we as hobbyists all need to really understand that the precious natural habitats that we ALL love so much offer a beauty, "order", and resilience all of their own, and that they evolved over time as the forces which act upon them except greater influence upon them.

Some of these forces are artificial and detrimental, like deforestations, siltation, runoff, and pollution. By making the effort to really understand how these habitats function in their un-adulterated state, we are gaining insights and appreciation that may help us do a better job at protecting them for future generations to enjoy.

Let's do a better job in the hobby of understanding each other. Let's do a better job of looking at Nature and appreciating the job it does, despite our predilection for wanting to  do things OUR way. Let's do a better job of being more open-minded, more creative within the context of what Nature does. Let's do a better job in the hobby of understanding each other. We're all better off together, working with each other to push the boundaries of this wonderful hobby.

And it all starts by looking at what happens to an aquatic habitat when any old log, branch, or root falls into it. To see, study, and understand that the aquatic environment is influenced by so many unique factors- many of which we can interpret and foster in our own aquariums, is the key. To give Nature the space to "breathe" within our tanks will take us to entirely new places in the hobby.

It's not only interesting...It's transformational! 

We just need to accept it. 

Stay creative. Stay honest. Stay open-minded. Stay studious. Stay together. Stay inspired...

And Stay Wet.

Scott Fellman

Tannin Aquatics