November 16, 2018


Friday Philosophy: "Functional Aesthetics"

Part of what I love about the aquarium hobby is the many different directions that we can choose to take. And, with so many hobbyists starting to get into this dark and earthy world that we play with, it's important to look at what we do in the context of aquarium hobby overall, and how this affects our understanding and expectations of this approach.

I think it starts with looking at the current "rules" of the aquarium game, and what their implications are.

As long-term readers of "The Tint" know, I tend to take an extremely dim view of "rules" that nature herself hasn't laid out. People ask me why this is, and I think it comes from my deep distrust of "them", and an overwhelming respect for the way Nature has created her ecosystem.

Some of the most offensive "rules", IMHO, tend to be those which dictate the way materials need to be laid out within an aquarium in order to conform to some sort of "style." Now, before you go on and rail on me, I'm not saying that you shouldn't take into consideration some artistic norms, with due consideration that we are working in confined spaces, etc. I'm not saying that utilizing some guidelines from the art world or design is a bad thing! There is a lot of very good stuff we can grab from that world. It's not "us versus them" by any stretch.

That being said, I can't help but think about how Nature forms the ultimate "prototype" for almost everything we do. And how we as a hobby seem to have sort of turned the other way for a long period of time and embraced a more "artistic" style as opposed to a purely "natural" one.

Don't get me wrong- I love artistic 'scaping, and like to incorporate it in the work that I do.  I'm not advocating that you go 360 degrees in the other direction and become obsessively "biotope-centric", either.

It's just that I have looked at the botanical stuff with more than just a nod to how they make the aquarium look, and I think we all need to understand that it's more than just about the pure aesthetics here. I understand why aquascapers embrace some of the theories of color, style, etc...but sometimes wonder if the "pervasiveness" of this mindset  in the hobby has prejudiced us to the point where we have created a "standard" for what we think nature looks like: Orderly, neat, colorful, proportioned.

As we know, Nature couldn't give a $%#@ about our perceptions of her work! 

Is there not also beauty in "randomness", despite our near-obsessive pursuit of rules, such as "golden ratio", color aggregating, etc? Surely there is some happy medium here?

I think so.

Just because last year's big 'scaping contest winner had the "perfect" orientation, ratios, and alignment of the "(insert this year's trendiest wood here) branch" within the tank, doesn't mean it's a real representation of the natural functionality of "randomness." 

In other words, just because it looks "good", it doesn't mean it's what nature looks like.

Or acts like, for that matter.

One of the things that we've noticed lately in the hobby, particularly in our sector, is a trend towards more "realistic" aquariums. Not just systems which look like natural environments; rather, systems which are modeled as much after the function of them as the aesthetics.

"Functional aesthetics."

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

We're seeing that not only do botanicals, leaves, and alternative substrate materials look interesting- they provide a physiological basis for creating unique environmental conditions for our fishes and plants. We're seeing fish graze on the life forms which live in and among the decomposing botanicals, as well as the botanicals themselves- just like in nature...And we are seeing the influence- aesthetically and chemically- that these materials assert on the aquarium's environmental parameters.

Some of the "next" things that I see our community working on are further explorations into understanding and replicating natural water parameters and what the implications are for our aquariums. I also see more developments in trying to recreate some aspects of natural "food chains" in our BWBS aquariums, by facilitating the growth and reproduction of fungi, microorganisms, and small crustaceans within our botanical "beds" and leaf litter.

"Functional aesthetics."

It's really great to see our community exploring some of these ideas that may not tie to any specific "type" of aquarium. In other words, the lessons we're learning from botanical-style aquariums can apply to a variety of aquarium endeavors, like breeding, biotope aquariums, rearing of fry, and oh yeah- aquascaping. We're moving beyond the "will it work?" mindset we collectively had about these tanks just a few years ago, and moving into a "what can we do with what we're learning" era! 

Yeah, for a good part of the first couple of years of Tannin's existence,  I spent a great deal of time worrying about how the idea of a carefully conceived hardscape slowly transforming by the actions of fungi, bacteria, and decomposition would "play" to my fellow hobbyists.  I was worried about potential mistakes and disasters that would befall fellow hobbyists if they pushed too hard, "freelanced" it a bit.

If they ignored the processes behind the aesthetics.

Fortunately, it hasn't happened all that much.

Yes, some of you may have experienced some disastrous results experimenting with botanicals- particularly when adding them en masse to an established, stable aquarium. I had a few bad outcomes in my early days of experimenting with this stuff, myself. There IS a learning curve- even now. Botanical-style aquariums are NOT plug-and-play systems. You can't simply dump a bunch of prepared seed pods and leaves into an established aquarium and expect "Instant Amazon." 

It doesn't work that way. 

And we're learning that, just because the water has a "tint" to it doesn't mean that you're achieving "natural" environmental characteristics in your aquarium. 

This is a concept that we need to embrace. There is a lot more nuance- a lot more things you need to do, observations you need to make, and stuff to learn in order to get there.

Really- there are no shortcuts. 

Now, all that being said, it's not just one big "science experiment", and that there is no room or "tolerance" for the "art" of it all. Absolutely not. 

You can enjoy botanicals and blackwater aquariums in as much or little "detail" as you care to venture into.  You can enjoy this or any approach however you want. I just think that there is a lot of misinformation about blackwater aquariums, botanicals, and their associated use, and I'd hate to see that taint the real enjoyment you can achieve by exploring in a more uninhibited fashion (with due respect to Nature's "rules" about the nitrogen cycle, stocking, etc., etc.- the basics of aquatic husbandry...

It's about expectations and understanding. If you're just looking for a cool aesthetic, that's okay. You simply need to understand what happens to botanicals when they are submerged in they break down, what they do to the appearance and environmental parameters of our tanks. 

It's the era of "Functional Aesthetics"- and yeah, you're right in the thick of things.

Enough philosophical ramblings for today...

Stay inspired. Stay excited. Stay curious. Stay diligent. Stay observant...

And Stay Wet.


Scott Fellman

Tannin Aquatics




November 15, 2018


Filtering through the filter process...

We spend a great deal of time contemplating the look and feel of our botanical-syle aquariums, and wrapping our head around the various "mental shifts" necessary to really appreciate and embrace this approach...You know, learning not to fear the tinted water, decomposing botanical materials, biofilm, detritus, etc. 

And that's really great. It's foundational.

However, one of the things we don't talk about as much as we should here is actually another foundational aspect of our aquarium practice: filtration.

Yeah, the ubiquitous, necessary, and highly important function of filtration in our aquariums is definitely something we as lovers of leaves and botanicals need to give a little thought to when we set up our systems. 

Of course, I could launch into a boring, been-there-done-that review on the various filtration types available in the hobby and what they do and blah, blah, blah...However, you wouldn't read it and you'd be yawning the whole time. I mean, there's a 50/50 chance you might be anyways, but hey...

Now, first- my "disclaimer" of sorts: I'm no filter "expert." I'm not an aquarium "gearhead." My thoughts on this topic are based, like everything I write- on my personal experience and ideas, laced with a healthy dose of "opinions" and stubbornness... 🤔

So, here's the "long and the short" of this topic:

You can use just about any type of filter available on your botanical-style blackwater/brackish aquarium. The real considerations, IMHO, are a) where in the water column you are bringing in water, and b) where the outputs are aimed. Oh, and c) what media you're using in the filter.

So, let's look a bit closer. 

I have used all sorts of filter systems on my BWBS style systems over the years, but the ones that I tend to use will surprise you...maybe. Maybe not.

As a reefer, I love my tanks with built in overflows and sumps.

(My friend Marc Levenson makes all sorts of badass sumps, look him up.)

I love sumps. I love them because:

a) You don't see any of the ugly shit (heaters, etc.) in the tank proper. Oh, and even those freakin' "Lily Pipes"- yes, I know that YOU may not think they're ugly, but I"m no fan of them as they are now. Why? We can have that discussion some other time, okay?

b) Sumps add water volume to your tank

c) Sumps provide an area where you can keep filter media, biological media, botanicals, wood, etc. to influence water conditions in the display. Like, if you hate the look of leaves and decomposing stuff in your display, but love the blackwater look and biodiversity, sumps are a good choice.

d) They rely on surface overflow weirs to supply water. Overflow weirs skim water from the surface, removing the film which accumulates and can interfere with gas exchange...Important when you have lots of botanicals in your tank breaking down, right?

"All in one" tanks, like my Innovative Marine "Fusion Lagoon" system, offer a great "hybrid" of a sump and an external filter, making an affordable, simple, aesthetically clean, easy-to-maintain-and-operate system.

Now, I realize that not everyone wants the logistics, challenges, and additional considerations (return pumps, space under the tank, etc.) which go along with the use of sumps. I also realize that the majority of freshwater hobbyists utilize glass aquariums without overflows and such, so there are numerous other options.

Enter the canister filters!

Where would the hobby be without Eheims, Fluvals, and all the other canisters out there? These are wonderful choices because they provide you so much flexibility. 

Flexibility is really important in what we do.

As is the ability to hide the "visuals" of ugly canister filters for obsessive types like me...there are plenty of approaches you could take...

And of course, they offer "functional flexibility"...You can keep botanicals, like various leaves, cones, catappa bark, "Fundo Tropical", etc.  in filter media bags/cartridges, again giving those of you who like the tinted water but not the botanicals and their associated decomposition, biofilms, and detritus- the ability to keep them outside of the display proper. 

Oh, and where the water comes back into the tank is pretty important.

IMHO, you should direct the return from canister filters near the surface, to create agitation and to facilitate gas exchange. Unlike pure planted aquariums, where there is a definite benefit from using those $&%#@@ "Lily Pipes" and such to return water well below the surface to preserve CO2, I personally believe that heavily-stocked botanical-style aquariums benefit from this surface agitation.

I mean, you can return some of the water towards the lower levels of the tank to keep things "stirred up" just a bit, without blowing shit all over the tank. (that's a technical term, by the way).

And of course, outside power filters do the same thing- keep everything relatively neat and tidy, and potentially outside of the tank if you like.

Oh, and sponge filters are great- and those Matten Filters- because they are primarily biological filters and are relatively easy to hide in displays...

Now, I have spent a fair amount of time alleviating the fears of you weirdos who don't want to see leaves and pods and such in your tank physically by explaining that you can just toss these things into your filter or sump! And of course, it goes without saying that you can utilize all of these filters with the botanicals present in the display. Like, duh.

The real "issue", if you want to call it that- with filtration vis a vis our BWBS-style tanks is what media you utilize. Again, I call on my reef keeping experience to tell you that I am a huge fan of activated carbon. I use it on every tank I set up- even the ones with the gnarliest (yes, it's a word- I'm from L.A.), darkest "tint"  imaginable. 

Yes, carbon can remove some of the tint and probably even some of the valued humic substances and other beneficial compounds exuded by botanicals. It's not selective. That being said, it all can remove impurities, like volatile dissolved organic compounds, urea, some metals, etc. It's valuable stuff. The key is to just not overdo it. Of course, if you want leaves and such in your tank, but not the tint- as we've discussed many times- just use the 'typical" dose of carbon and you have the best of both worlds- at least aesthetically.

(Yes, I stole another pic from our good friend, George Farmer, of his latest tank which demonstrates this beautifully!)

Better as chemical filtration media would be stuff like specialized ion-exchnage or "organic scavenger resins" and zeolites- stuff which requires more research, trial and error, and testing. But it is possible, at least in theory, to incorporate filtration media which removes the undesirable pollutants and retains the desired humic substances and tannins. Oh, and proper biological function in low pH systems, fostering the "biome" of these tanks.

These things are are all something we will see more of in the me.

In the mean time, you can use materials like carbon, Poly Filter, Purigen, etc. to do the trick; just be aware of the way they work and what they will do. If you go "full power" (ie; the typical manufacturers' recommended "dose"), you'll have a clear tank- if that's what you want.

And of course, we recommend mechanical filtration media, like "noodles", filter pads, floss, etc., and of course, biological media.

In summary- my advice is to use whatever type of filter system you like. The key is how you utilize it- what media you employ, where you draw the tank water into it, and where it's returned.

And, like with everything else we play with in this arena, there is plenty of room for experimentation, innovation, and even breakthroughs in regards to filtration in our BWBS systems. 

This is a real "open source" component of what we do. An invitation and opportunity for YOU- the working aquarist- to make a big impact on the hobby, fostering benefits perhaps as yet not understood...

So, yeah- use what works for you, benefits your fishes, and creates the best outcomes. At its best, this is a summary of ideas and hopefully, a brief dossier on potential things to do in the future.

Stay engaged. Stay bold. Stay curious. Stay inquisitive. Stay innovative...

And Stay Wet.


Scott Fellman

Tannin Aquatics 





November 14, 2018


There will be decomposition.

Our crowd thinks a bit differently than most in the hobby, I'd venture to say.

We're advocating the addition of botanical materials to our aquariums as a matter of course, for the everyday purpose of replicating, to some extent, the natural processes which occur in the wild habitats of our fishes. 

And we spend a great deal of time examining the processes which occur when leaves and other botanicals are added to the aquarium. This is important, not only from an aesthetic standpoint, but from an ongoing functional/operational standpoint.

It definitely differs from our 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 specifically to facilitate breeding.

We understand- or are attempting to understand- the impact on both our aquariums' ecology and the husbandry involved. It's the idea of creating an aquascape that is not only good-looking and interesting, but one which provides environmental enrichment and ecological advantages for its resident fish population.

It involves change.

It involves decomposition.

Yeah, it's sort of a different approach.

And I think we can embrace it further by considering how the botanical materials we select for our aquariums "behave" upon submersion into water. A carefully constructed botanical hardscape, IMHO, should have some-more-or-less "permanent" things, like rocks and driftwood, complemented and be enhanced by "degradable" items, such as Catappa, Guava, and other leaves, as well as the "softer" pods and such.

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

Leaves and such are simply not permanent additions to our 'scapes, and if we wish to enjoy them in their more "intact" forms, we will need to replace them as they start to break down. 

This is not a bad thing.

Much like flowers in a garden, leaves will have a period of time where they are in all their glory, followed by the gradual, inevitable encroachment of biological decay.

At this phase, you may opt to leave them in the aquarium to enrich the environment further and offer a new aesthetic, or you can remove and replace them with fresh leaves and botanicals. Again, this is very much replicates the process which occur in nature, doesn't it? Stuff either remains "in situ" as part of the local habitat, or is pushed downstream by wind, current, etc.

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

Some hobbyists have commented that, as their leaves and botanicals break down  the scape as initially presented changes significantly over time. Wether they know it or not, they are grasping "Wabi-Sabi"...sort of. One must appreciate the beauty at various phases to really grasp the concept and appreciate it. To find little vignettes- little moments- of fleeting beauty that need not be permanent to enjoy.

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

And, if you look at them objectively and carefully, these assemblages are beautiful.

This is not something new or previously unconsidered by the hobby, but it's something we don't give much thought to, I think.

We just plug along, feeding our fishes, doing water exchanges, and growing plants. We tend to our aquascapes, and watch things grow. And, over time, even the most diligently-maintained aquariums tend to look significantly different than when they did when they were first assembled.

It's how natural systems go.

There will be change. There will be decomposition.

Stay observant. Stay diligent. Stay curious. Stay in synch. Stay thoughtful...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


November 13, 2018


"Plug and Play?" No Way!

With so much going on in our botanical-style aquarium world, it's nice to continue to revisit some of the important concepts that will yield success for the widest variety of hobbyists.

Now, let's be clear: There is no "plug and play" formula to follow- only "procedure." Only recommendations for how to approach things. We sound a bit like the proverbial "broken record"; however, like so many things in aquarium-keeping, our "best practices" are few, simple and need to be repeated until they simply become habit:

1) Prepare all botanicals prior to adding them to your aquarium. 

2) Add botanical materials slowly and gradually, assessing the impact on your aquarium environments and inhabitants.

3) Either remove botanical materials as they break down (if that's your aesthetic preference), or replace them when they reach a point where they are no longer providing the aesthetic and environmental conditions that you desire.

4) Observe your aquarium continuously.

By observing and assessing on a continuous basis, you'll get a real feel for how botanicals work in your aquarium.  Point #3 is the real "finesse" part of the equation...the nuance, the subtle, yet noticeable adjustments and corrections we make to keep things moving along nominally- sort of like pruning in a planted tank, or weeding a's a process.

In fact, the entire experience of a blackwater, botanical-style aquarium boils down to a process and a pace that helps foster the gradual, yet inexorable "evolution" of the aquarium. And let there be no doubt- a botanical-style aquarium does "evolve" over time, regularly and steadily changing and progressing. As we've mentioned before, it might be the perfect expression of the Japanese concept of "wabi-sabi", popularized by Takashi Amano, which is the acceptance of transience and imperfection.

And the patience to allow your system to evolve. It's absolutely the most essential skill to have if you're going to work with botanical-style aquariums. Period. There are no shortcuts, major "hacks", or ways to dramatically speed up nature. Why would you want to? 

If you're into tropical fish keeping, it's almost a necessity to have this sort of patience, isn't it? I mean, sure, some of us are anxious to get that aquascape done, get the fishes in there, fire up the plumbing in the fish room, etc. However, we all seem to understand that to get truly good results- satisfying, legitimate results- things just take time.

I'm sure that you know this already, however. I hate using myself as an example, but I think perhaps reflecting upon how I adopted this mindset might be helpful.

I know that this mindset of crazy patience came to me over time. It was an evolving thing. I think that in my case, it might have come about because, when you’re a kid, you have a 10-gallon tank and like $5.67 in change that you’ve painstakingly saved for months to spend. You need to be absolutely sure of your purchases.

I was. I had no choice but to be very thorough! No sense in rushing things.

This mindset has stayed with me for decades.

I'm not looking for instant gratification.

I know that good stuff often takes time to happen. I'm certainly not afraid to wait for results. Well, not to "just sit around" in the literal sense, mind you. However, I'm not expecting instant results from stuff. Rather, I am okay with doing the necessary groundwork, nurturing the project along, and seeing the results happen over time.

A "long game." 

That's what we play here.

And understanding that what we do in the blackwater, botanical-style aquarium world requires these skills above almost anything else. I mean, look at what we do: We add leaves and seed pods to our aquariums, for the expressed purpose of having them break down.

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

As if we don't see that or understand why...

Mental shifts are required from everyone who plays in this arena.

Now, of course, an aquarium is not an open, natural system, yet if well-managed, it can function beautifully for years and years, like any other approach.

For some reason, when we first started touting this approach (NO, we did not "invent" it- and will never claim that! NO ONE did.)

There are really two huge factors that have been touted as the reason for not doing what we are doing over the years: One is based on the prevailing mindset of what the hobby thinks a tank should look like, and the is other based on a perception that there is a negative the environmental impact on a "carefully constructed aquarium environment." Both are valid points, I suppose- although the comical part to me is the automatic assumption that we're not working with "carefully constructed aquatic environments" here.

Why? Because the water is...brown? Because we throw leaves and twigs and botanicals into our tanks and sort of eschew the artificially rigid style that is so many people's perception of what aquascaping is?


After years of experimenting with leaves, botanicals, and other natural materials in aquariums, and with a growing global community of hobbyists doing the same daily, the mental roadblocks to this approach arestarting to fall. We're seeing all sorts of tanks being created by all sorts of hobbyists, which in years past would garner far more hushed whispers and criticisms than any gasps of envy.

And again, it boils down to observing many basic tenants of aquarium keeping.

Now, the moniker "organics" that we have used as a metaphoric "red flag" to discourage throwing this stuff into tanks in years past is still important to understand. Sure, organics can accumulate and even be problematic- if you don't have necessary control and export processes in place to deal with them. What would these processes be?

Well, to start with: Decent water movement and filtration, to physically remove any debris. Use of some chemical filtration media, such as organic scavenger resins, which tend not to remove the "tint", but act upon specific compounds, like nitrate, phosphate, etc.

And of course, water exchanges. Yeah, the centuries old, tried-and-true process of exchanging water is probably the single most important aspect of nutrient control and export for any system, traditional, botanical, etc. There is no substitute for diluting organic impurities through regularly-scheduled water changes, IMHO.

This isn't some revelation.

I'll say it yet again: In my experience, there is nothing inherently more challenging or more dangerous about these types of tanks than there is with any other speciality system. The fact that the water is brown doesn't mean that a well-managed tank is any closer to disaster than any well-managed clear water system.

There's no magic here.

We simply need to do the work necessary to keep our aquariums operating in a healthy state. Nope, nothing new here. In my opinion, NO aquarium of ANY type is "set and forget"; do that and you'll be in for a rude awakening with a blackwater, botanical-style tank- or any tank. You can't really take that approach in this hobby, IMHO.

That being said, I commend many of you for forging ahead with new ideas and this approach that might not be familiar to you. Moving from the theoretical to the functional takes some courage, imagination, and most of all..impulse. When it comes to trying out exotic new concept aquariums, guys like me (as you all know by now) just need to get the damn thing started and stop musing on about it.

Others go full speed ahead...damn the torpedoes! Regardless, self-awareness is important! I think it's in my nature to get a bit too deep into the planning. The challenge for me is not to get so bogged down in an endless cycle of "analysis paralysis" that I never get projects off of the drawing board!

Don't get into this rut, okay? Understand what's involved, what's required of you as a hobbyist, and move forward. Just remember a few things:

It's not a "plug-and-play" proposition. It requires some effort, thought, observation, and patience...

So, yeah...I'm glad you're here. Glad you made that mental shift...and have the courage to try something that might be new for you!

Enjoy. Learn. Practice. Explore. Share.

Stay bold. Stay creative. Stay relentless. Stay undeterred. Stay dedicated...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


November 12, 2018


First foods, revisited...

It's funny in the hobby how that the more things change, the more they often seem to simply be evolutions from older practices. For example, the rearing of fish.

It all starts with food, right?

For pretty much as long as anyone caudal remember in the hobby, we've cultured living organisms to feed our fry after hatching. And, if you've been in the hobby more than a few years, you've likely heard of this valuable, easy-to-culture live food called "Infusoria."

Remember that word?

It's one of those aquarium world "catch-alls"; a sort of "throwback", if you will, from a "gentler, kinder era" in aquaristics. A time when under gravel filters, freeze-dried foods, and airmail of tropical fishes from Florida to your local airport were considered seriously badass, state-of-the-art, cutting edge things.

"Infusoria" may be described as a real "catch-all" term for small aquatic organisms, like euglenids, protozoa, unicellular algae, tiny invertebrates, and that are commonly found in freshwater environments, like ponds, creeks, and drainage ditches, used as a first food for tropical fish fry. Sometimes, it's referred to as "green water" in older hobby literature- an even more charming, albeit kind of vague descriptor!

In modern formal biological classification, the term "infusoria" is considered an antiquated, obsolete descriptor, as  most of the organisms previously included in the collective term "Infusoria" are assigned to a different assemblage of taxonomic groups.

Nonetheless, it's a charming, albeit somewhat antiquated term that is still used in aquarium circles to describe the tiny organisms that arise when you soak some blanched lettuce, vegetable skin, or other plant matter in a jar of water. They're perfectly sized for young tropical fish fry as the first food when they are free swimming. In fact, at around 25-300 microns, these organisms are consumable by most fishes as soon as they've absorbed their yolk sac.

Yummy ( Well, if you're a little fish...)!

Sounds good, but how do you "make" the stuff?

Traditionally, it was done in the most low-tech way, which you know I love: You would take some blanched lettuce leaves, old flower clippings, hay, etc. etc. and basically let the stuff decompose in water, and after several days, a smelly solution of cloudy water will arise, driven by bacteria. Ultimately, after a few more days, the water will clear when creatures like Paramecium and Euglena arrive on the scene and consume the rampant bacteria population.

Voila! In theory, you have an "infusoria culture."

Well, yeah, but the problem is, the density of desirable animals to plain old water is pretty low when you culture this way, and you'll most likely be "feeding" your hungry fry with drops of stagnant water, little more. Kind of yucky...The more modern approach would be to obtain a pure starter culture of Paramecium from an online biological supply house (yeah, their are plenty of 'em- just do a Google search). Here's my fave. Paramecium average around 150 microns in size- perfect for free-swimming tropical fish fry!

You can use the aforementioned decomposing lettuce as a start, or you can elect to be a bit more clean and modern and use brewer's yeast (which comes in tablets) that you'd use at a rate of like 1/2 of a tablet to a 1 liter bottle. Sure, there are probably more exact numbers to employ, but this is a hobby, right? I'm sharing what worked for me, so your mileage may vary. You'd also use a few grains of wheat, which you can grab at the local health food store (or supermarket, for that matter) to help kick start things. Don't overdo either, as you'll end up with a much more stinky culture as a result. And in the hobby/life balance, "stinky"=bad. 🤔



Trust me on that!

You might notice a scum on the surface, and perhaps a bit of odor to the water...but you're an aquarist, so you're used to smelly wet stuff, right? And the water will take on a bit of a faint brownish or very light greenish color- totally normal.

After about 4-5 days, you should take a few drops of water from your culture (beneath the "surface scum") and examine them under bright light with a magnifier. You'll be able to see some little, tiny sliver-like "things" (I Know, a very scientific descriptor) wiggling around in the water. If you're hardcore like me, you'd look at them under your cool hobby microscope (a totally fun tool for the aquarist, BTW) for more accuracy!

This tells you it's time to rock and can feed your baby Tetras, Barbs, etc. right away, by dropping like 40-50ml of culture solution into your 5 gallon rearing tank. It's actually no big deal if you add more, because these organisms are harmless, and would naturally be found in water with fishes (albeit at a lower density). Since you're doing regular water exchanges in your rearing tank, you can minimize pollution along the way. Feed several times daily, and you'll be surprised how quickly the fry learn to recognize and attack them.

Sure, there is really not all that much involved in the process of raising "infusoria" than we've outlined here. Cultures of Paramecium are used extensively in labs to rear larval fishes, because they are an economical, nutritious option for newly-free-swimming fishes to feed on.

So, like many things in the hobby- the approach may have changed, but the idea remain the same- using whatever means we have at our disposal to create the best possible outcomes for our fish efforts!

Now, no discussion of rearing our little fishes would be complete without revisiting the idea of a botanical-influenced "nursery" tank for (blackwater) fishes for a number of reasons:

First, as we've discussed many times, the humic substances and other compounds associated with leaves and other botanicals, when released into the water, are known to have beneficial health impact on fishes. The potential for antimicrobial and antifungal effects is documented by science and is quite real. Wouldn't this be something worth investigating from our unique angle?

I think so!

Additionally, rearing young fishes in the type of environmental conditions under which they will spend the rest of their lives just makes a lot of sense. Having to acclimate young fishes into unfamiliar/different conditions, however beneficial they might be, still can be stressful to them.

So, why not be consistent with the environment from day one?

Finally-and this is the aspect we're going to focus on the most here- because it ties into the "infusoria" thing...the breakdown and decomposition of various botanical materials provides a very natural supplemental source of food for young fishes, both directly (as in the case of fishes such as xyliphorous catfishes, etc., and indirectly, as they graze on algal growth, biofilms, fungi, and small crustaceans which inhabit the botanical "bed" in the aquarium.

Now, this is pretty interesting stuff to me.

Everyone has their own style of fry rearing. Some hobbyists like bare bottom tanks, some prefer densely planted tanks, etc. I'm proposing the idea of rearing young fishes in a botanical-style blackwater aquarium with leaves, some seed pods, and maybe some plants as well. The physically and "functionally" mimic, at least to some extent, the habitats in which many young fishes grow up in.

My thinking is that decomposing leaves will not only provide material for the fishes to feed on and among, they will provide a natural "shelter" for them as well, potentially eliminating or reducing stresses. In nature, many fry which do not receive parental care tend to hide in the leaves or other biocover in their environment, and providing such natural conditions will certainly accommodate this behavior.

Decomposing leaves can stimulate a certain amount of microbial growth, with infusoria and even forms of bacteria becoming potential food sources for fry. I've read a few studies where phototrophic bacteria were added to the diet of larval fishes, producing measurably higher growth rates. Now, I'm not suggesting that your fry will gorge on beneficial bacteria "cultured" in situ in your blackwater nursery and grow exponentially faster.

However, I am suggesting that it might provide some beneficial supplemental nutrition at no cost to you!

And it's the same with that beloved aquarium "catch all" of infusoria we just talked about...These organisms are likely to arise whenever plant matter decomposes in water, and in an aquarium with significant leaves and such, there is likely a higher population density  of these ubiquitous organisms available to the young fishes, right?

Now, I'm not fooling myself into believing that a large bed of decomposing leaves and botanicals in your aquarium will satisfy the total nutritional needs of a batch of characins, but it might provide the support for some supplemental feeding!

I'd take the concept even a bit further by "seeding" the tank with some Daphnia and perhaps some of the other commonly available live freshwater crustaceans, and letting them do their thing before the fry arrive. This way, you've got sort of the makings a little bit of a "food web" going on- the small crustaceans helping to feed off of some of the available nutrients and lower life forms, and the fish at the top of it all. 

Now, granted, I'm romancing this and perhaps even over-simplifying it a bit. However, I think that there is a compelling case to be made for creating a rearing tank that supports a biologically  diverse set of inhabitants for food sources.

The basis of it all would be leaves and some of the botanicals which seem to do a better job at recruiting biofilms- the "harder shelled" stuff, like "Savu Pods", "Jungle Pods", Coco Curls", "Capsula Pods", etc...I think these would be interesting items to include in a "nursery tank." And of course, they provide shelter and foraging areas and impart some tannins into the water...the "usual stuff."

Just another one of those ideas that would be fun to experiment with. Certainly not the "ultimate" fry rearing system...but I think one we have legit basis for playing with more and more.

I say to the breeder who may, for one reason or another, decided to use different foods- to give the "old school" method a try once in a while, not just because it works- but to help keep alive a direct link to the past of our fish keeping heritage, with a more modern approach applied.

And, for that matter, let's continue to push into some new ground with the "botanical-style nursery" approach, too!

Until next time, watch those little creatures swim, feed those fry...Go old school. And try a new twist, too!

Stay creative. Stay dedicated. Stay engaged. Stay devoted...

And Stay Wet.


Scott Fellman

Tannin Aquatics


November 11, 2018


Blackwater, Bettas, and Botanicals with Rachel O'Leary!

With the blackwater, botanical-style aquarium becoming a whole lot more of an accepted "approach" to specialized fish keeping, as opposed to just a "fad" or "trend", it's wonderful to see some of the true legends of our hobby sharing their experiences with this stuff!

One of our fave all-time aquarists is Rachel O'Leary, aka "msjinkzd" - who has contributed so much to this hobby for so many of us over the years. Her breeding efforts, emphasis on education and sharing of techniques and "best practices" have created many, many successful aquarists and devoted fans. 

And, as both a botanical-style aquarium enthusiast (yeah, she was tinting tanks long before it was considered "cool!") and breeder (okay, and bona-fide aquarium superhero...)Rachel is in a unique position to share her long personal experience and explain both the benefits and the aesthetics of this type of tank! 

Rachel recently acquired some botanicals from us in order to accent an already beautiful scape by Ricky Chawla for wild Bettas- long a favorite of many of us! And as she does, Rachel created a very cool video sharing the experience, offering some practical approaches, and some good 'ol fashioned education on the process and rationale for utilizing botanicals! 

As she explains, "...the aquarium houses 6 wild Betta imbellis, 14 Chili Rasboras, and a whole host of amazing plants and botanicals!"

The result is fantastic! Check it out!   

We hope you derive as much inspiration, education, and enjoyment from this video as we did!

Be sure to tell Rachel what you think of this tank, and share the video with others who might appreciate a little inspiration from one of the aquarium hobby's true ambassadors! 

Stay inspired. Stay curious. Stay creative. Stay bold...

And Stay Wet!


Scott Fellman

Tannin Aquatics 



November 11, 2018


"Tintmail", revisited...

From time to time, in between the questions about biofilm, biotopes, and leaf litter, I'll get questions asking all sorts of stuff. 

I love it! 

Here are a few, from recent email/DMs, which may be of interest to you...

Which botanical material we recommend to keep your water that dark brown tint?: I have a few recommendations, based on my experience and (admittedly biased) taste. So, here are my fave "tint-producing" no particular order:

Catappa Bark

Sappanwood Pods

"Ceu Fruta"

Texas Live Oak Leaves"

Coco Curls

"Rio Fruta"

Alder Cones 

Banana Stem Pieces

Encontro Pods

Oak Branches ("Twenty Twigs")

Magnolia Leaves

Catappa Leaves

Mangrove Leaves

Guava Leaves

The caveat: These are materials which, IMHO really seem to produce the most rich-colored water and effects. Now, sure, there are probably 40 other items we offer that can accomplish the same task; these ones just seem to do it faster and with greater effect. Of course, if you're running activated carbon or materials like Purigen in your filter, these media will minimize or eliminate almost entirely any coloration these botanicals impart into the water.

"Pro Tip": You can usually get some indication as to what color and how intense the color a given botanical will impart into your water when you prepare it...That initial burst of tannins and other coloring compounds is immediately obvious and probably quite helpful in determining the color "palette" to expect!

My personal fave "tint bomb?": Well, scientific research indicates that Catappa Bark seems to have a very concentrated quantity of tannins and other compounds bound up in its tissues, which means you don't need to use a ton of the stuff in most aquariums to enjoy the benefits of its capabilities (the imparting of tannins and humic substances, and the visual tint). We offer three different varieties, because I'm obsessed with the stuff! 

I personally feel that it "lasts" a long time (a month or two, at least) in terms of imparting color into the water. And it looks cool. Yes, it actually has an incredible aesthetic that makes it even more attractive from multiple standpoints. 

Just how long does this botanical stuff last?: Many of the less durable botanicals will last several months, at least "structurally", but might be far more limited in terms of their  impartation of color to the water- perhaps a few weeks in many cases.

What do I need to do to keep my blackwater tank "dark?": Monitoring pH, visual tint, nitrate and phosphate are but a few of the things you should undertake as part of the active management of a blackwater aquarium. Water exchanges are the other. And regular replenishment of botanicals. To me, that's a huge part of the fun. We offer general guidelines and "best practices", but really, each tank is a "one off", and more customized approaches are the way to go. Again, this is what makes our little sector of the hobby so compelling, IMHO.

What's your number one concern about botanical-style aquariums?: I'm still concerned about the newbie to our botanical-style aquarium practice going too fast- dumping a huge amount of botanical materials into an established, relatively stable aquarium, and causing a massive increase in CO2 and a level of organic material that overwhelms the ability of the resident denitrifying bacteria population to break down the organics...

The human element.

A disaster that can ensue...

That sort of thing is always still possible. And it's within our control. That's what you read blog after blog written by me urging you to go slowly. To observe your tank and fishes. And to test the water regularly...and do regular water changes as part of your husbandry regimen.

The usual stuff.

And your best overall hobby advice?: Just because you reject the "status quo", the popular, or the safe, doesn't mean that you're wrong. Just because your idea of an aquascape features soil and decomposing leaves instead of a cliche-ridden "Middle Earth Hobbit-Forest" doesn't mean you're not creating aspirational work. Just because you're breeding Danios instead of this month's "Apisto of The Month" doesn't mean you're not talented. Just because you're specializing in Anacharis instead of Bucephalandra doesn't mean that you don't have "plant game."


Be you.

That's it for this round of "Tintmail..."

Stay innovative. Stay curious. Stay diligent. Stay consistent. Stay unbridled by convention...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

November 10, 2018


Beyond the pretty looks...The synergy of life and aesthetic

It's fun how thought processes evolve in the hobby. 

In our world of blackwater/botanical-style aquariums, we're now at a phase where enough people have gotten through the "Will this kill my fish?" part of the equation, and we've now moved on to "How can I facilitate maximum benefits to my fishes with a blackwater, botanical-style aquarium?"

Many of us are even moving beyond just the pretty look of the botanical-style aquarium, and moving into a deeper stage of understanding how our aquariums function as miniature ecosystems.

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

I have long been one the belief that if you decide to let the botanicals remain in your aquarium to break down and decompose completely, that you shouldn't change course by suddenly removing the material all at once. 

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

We add leaves and botanicals periodically, not just for an aesthetic "refresh", but for a "re-charge" of the biome within our tanks. This is a fascinating spect of the botanical style aquarium. It facilitates the cycle of growth, nutrient accumulation, and decomposition. It becomes not only part of our practice, but it's part of the "system" we are trying to facilitate.

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

And we have to accept nature's input here.

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

Nuance. Art. Challenge. Fascination.

Beyond the pretty looks. That's where the real magic lies.

Stay observant. Stay curious. Stay appreciative. Stay open-minded. Stay introspective. Stay patient...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

November 09, 2018


Brown crush. Falling further in love...

Another week in the world of the blackwater/botanical-style aquarium movement. More excitement. More new tanks. More "love" for this unique aesthetic and the function and fascination it brings with it.

And of course, with more newcomers come more questions!

One of the top questions we field here is, "Can I have lots of botanicals in my tank without brown water?"

And of course, the answer is YES!! 

This is obviously a concern for many people, and I get it.  

Happily, we are seeing a large influx of hobbyists interested in utilizing botanicals in their aquariums. Many, however, are accustomed to the clear water look. The so-called "Nature Aquarium Syle" and many in the really hardcore aquascaping crowd don't really have a "protocol" for incorporating or even considering botanicals in their scapes, let alone, the tinted water, and it makes sense. 

We hope to change that!

With more hobbyists from different "worlds" starting to play with botanicals and such, it's only logical for us to address these concerns! We're excited to have you guys playing with us!

So, just how do you get rid of the tint?

It's ridiculously easy. Just use chemical filtration media in your filter. Specifically, activated carbon or my fave, Seachem Purigen.

Yeah, it's that easy. This way, you can have all of those sexy botanicals in your tank, and none (or very, very little) visual tint.


And, as more and more hobbyists embrace the use of botanicals in their aquaria, we're seeing more and more tanks with a golden brownish-colored "tint" to the water. A lot of people are starting to take to it! Yet, there is a bit of confusion as to what it represents.

So, let's be clear (arghhh!) about one thing:

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

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

Of course, the water may have a lower pH and general hardness, and a suite of other organic compounds and such, but these factors typically have no real bearing on the visual clarity of the water.

That being said, one of the things you might notice right from the start is that botanical-laden aquariums occasionally seem to have an initial "haze" that is slow to clear. Now, part of this is no doubt due to the breakdown of the leaves, pods, etc. that we use: Surface dirt, lignin, and other compounds, bound up in the tissues of the botanicals, released into the water upon the initial submergence of these materials. And the fact that many of us tend to not use a lot of chemical filtration media in our tanks might have some impact on that, too.

This "haziness" or "turbidity" is not necessarily a bad thing, nor indicative of a problem. Not in our botanical-laden systems, typically. Rather, it's a sign that the materials we use are interacting with the aquatic environment. Another reason for this "haziness" could be a burst of microorganism/bacterial growth, which impacts the visual clarity as populations multiply rapidly in the "fertile" environment of a botanical system, with its wealth of organic materials supplied by the decomposing matter upon which these life forms feed.

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

Now, when you think about it, the botanical-style aquarium sort of falls into that category, huh? Leaves and botanicals certainly add to the organic load, and are most definitely materials which accumulate within the tank, right? And they look very different than what we are used to seeing in contests and "Vogue-esque" Instagram posts, right?

Blackwater tanks just look different. 

The water turns brown.

We've rehashed that like 4,000,000 times here.

Is this a negative? 

If you look at a lot of the underwater photos and videos taken in the natural habitats of our fishes that, thankfully, are becoming more and more popular and abundant than ever, you see a lot of "stuff" in the water column, on the bottom, etc.  And the water is not always crystal-clear blue white, right? It's...well, brown. Natural streams are not always the pristine-looking "nature aquarium" subjects of our dreams, are they?

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

And part of this "something" is accepting that the appearance is a visual/functional manifestation of the processes going on in your aquarium. And again, it's something not everyone likes. It's something that many might perceive as "dirty", "messy", and just plain ugly. 

And, perhaps even more important, the idea of throwing things like leaves and seed pods into a tank- a carefully managed artificial world, seems on the surface like simply "polluting" what was long suggested should be as pristine a system as possible.

And that brown water= "dirty", right?

Yeah. A lot of aquarists still equate tannin-stained water with "dirt." And curiously, with them being somehow more difficult to maintain. And really, blackwater/botanical-style aquariums are no more difficult than pretty much any other "style" of aquarium; they simply require an understanding of what makes them tick, and how to optimize maintenance activities to facilitate their long-term success.

Oh, and the understanding that the color of the water does not equal "dirty" or "difficult." 

Yet, I still  hear this a lot when I speak at clubs, showing hobbyists the wonders of the blackwater aquarium world. It's still kind of hard for many to get their heads around, despite us showing videos and pics up the ass of all sorts of wild blackwater habitats.

I know, I know- an aquarium is not an open, natural system, yet if well-managed, it can function beautifully for years and years.

Yet some hobbyists still perceive blackwater aquariums with botanicals as...ugly. And lately, I hear it called a "fad" or "trend" by some, which makes me laugh. (Nature doesn't play with "trends...")

It's becoming something we are more aware of. More exposed to, for better or worse. Some find it repugnant. Others find it an amazing area to explore.

Differences of opinion abound.

And that's perfectly fine. We all have our definition of beauty. Yet, we do carry a sort of "clearwater prejudice" in our fish-keeping "genes", right? 

I think so.

It's almost like our idealized aesthetic perceptions of what we feel water should look like in an aquarium have conditioned us as a hobby to sort of gently disregard what it truly looks like in the habitats from which our fishes evolved, and why it's important to their health. Now, I'm certainly not asserting that keeping fishes from blackwater habitats in a crystal-clear aquarium is somehow going to ruin their vitality or render them susceptible to many illnesses, or that providing "blackwater" conditions is some sort of "miracle concept" that will lead to unimagined success.

That's just too hyperbolic, IMHO.

However, I'm at least curious about how much better our animals might do long-term (I'm talking decades in captivity of being bred, etc.) if maintained in conditions that more-or-less replicate the waters from which they evolved. We've seen a lot of Discus, Betta and Apistogramma breeders utilize these types of conditions in their aquariums for many years, and their successes have been obvious.

And what's exciting is that we are still starting to see hobbyists equate the way natural ecosystems provide for the life forms which reside in them and how many factors contribute to their success. Like so many things in nature, the complexity of blackwater habitats is more than what meets the eye. This creates many opportunities for hobbyists to create amazing aquariums!

Chemically, biologically, and ecologically, blackwater habitats are a weave of interdependencies- with soil, water, and surrounding forest all functioning together to influence the lives of the fishes which reside within them. No single factor could provide all of the necessary components for fish populations to thrive. 

And they simply look different. Yet, amazingly natural-looking, and we hope, compellingly beautiful.

To replicate these unique habitats and the function and aesthetics which they bring requires some observation, open-minded experimentation, and a sense of adventure! 

And, perhaps, a little love for that brown water! 

Stay excited. Stay inspired. Stay open-minded. Stay educated...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

November 08, 2018


Getting to the bottom of...the bottom. "Substrate Enrichment", Part 157...

Yeah, I know, we're back to the bottom once again, aren't we?

It's something that I keep coming back to, because the idea of utilizing botanicals in your aquarium substrate keeps tantalizing me with its performance and potential benefits.

As I've obsessively reported to you, I recently set up a small tank in my office for the sole purpose of doing damn near the entire substrate with leaves and twigs- sort of like in nature. There is less than approximately 0.25"/0.635cm of sand in there. I went from throwing in wood to make it look "cool", to ultimately yanking out everything but the leaves and twigs on the bottom. That's the whole "scape." What we in the reef world call a "no scape." 

Leaves and a shoal of Parachierdon simulans. 

Nothing else.

And the interesting thing about this tank is that it is one of the most chemically stable, low-maintenance tanks I've ever worked with. It's held a TDS of 12 and a pH of 6.2 pretty much from day one of it's operation. It cycled in about 5-6 days. Ammonia was barely detectible. Nitrite peaked at about 0.25mg/L in approximately 3 days. 

Now, the point of this piece is not to drop a big old "humble brag" about some new tank I started. The point is to show what I think is an interesting "thing" I've noticed about this tank. Stability and ease of function.

I was quite astounded how a new tank could go from dry to "broken in" in a week or so. And not just "broken in" (ie; "cycled")- like, stable. I don't usually do this, but I tested all basic parameters every day for the first 3 weeks of the tank's existence, just to kind of see what would happen.

The interesting thing about a tank like this is that it relies on leaves in a way that I have rarely done before. Yet, I had complete confidence that it could work just fine. I'm not some "visionary" here- I'm just a guy who's played with blackwater/botanical-style aquariums for a long time and has developed a certain degree of comfort with them. Many of you are in the same position.

What goes on in an aquarium with botanicals- or leaves, in this instance as the total  "substrate" or "hardscape", as the case may be, is that they become the basis for biological activity in the tank. As we have discussed a million times here, as botanicals break down, they recruit bacteria, fungi, and other organisms on their surfaces.

What I am starting to feel more and more confident about is postulating that denitrification occurs in a system with a layer of leaves and botanicals as a major component of the tank.

Now, I know, I have little rigorous scientific information to back up my theory, other than anecdotal observations and even some assumptions. However, there is always an example to look at- nature. 

Of course, nature and aquariums differ, one being a closed system and the other being "open." However, they both are beholden to the same laws, aren't they? And I believe that the function of the captive leaf litter bed and the wild litter beds are remarkably similar to a great extent.

The thing that fascinates me is that, in nature, leaf litter beds perform a similar function; that is, fostering biodiversity, nutrient export, and yes- denitrification. Let's take a little look at a some information I gleaned from the study of a natural leaf litter bed for some insights.

In a slow-flowing wild Amazonian stream with a very deep leaf litter bed, observations were made which are of some interest to us. First off, oxygen saturation was 6.7 3 mg/L (about 85% of saturation), conductivity was 13.8 microsemions, and pH was 3.5.

Some of these parameters (specifically pH) are likely difficult to obtain and maintain in the aquarium, but the interesting thing is that these parameters were stable throughout a months-long investigation.

Oxygen saturation was surpassingly low, given the fact that there was some water movement and turbulence when the study was conducted. The researchers postulated that the reduction in oxygen saturation presumably reflects respiratory consumption by the organisms residing in the litter, as well as low photosynthetic generation (which makes sense, because there is no real algae or plant growth in the litter beds). And of course, such numbers are consistent with the presence of a lot of life in the litter beds.




Microscopic investigation confirmed this- it revealed that the leaf litter was heavily populated with fungi and other microfauna. There was a significant amount of fish life. Interestingly, the fish population was largely found in the top 12"/30cm of the litter bed, which was estimated to be about 18"/45cm deep. The food web in this type of habitat is comprised largely of fungal and bacterial growth which occurs in the decomposing leaf litter. 

Okay, I"m throwing a lot of information here, and doing what I hope is a slightly better-than-mediocre attempt at tying it all together. The principal assertions I'm making are that, in the wild, the leaf litter bed is a very productive place, and has a significant impact on its surroundings, and that it's increasingly obvious to me that many of the same functions occur in an aquarium utilizing leaf litter and botanicals.

Enriching a substrate, or composing an entire substrate of botanicals and leaves is a very interesting and compelling subject for investigation by hobbyists.

So, three areas of potential investigation for us:

*Use of botanicals and leaves to comprise a "bed" for bacterial growth and denitrification.

*Understanding the chemical/physical impact of the botanical "bed" on an aquarium. (ie, pH, conductivity, etc.)

*Utilization of a botanical bed to create a supplemental food source for the resident fishes.

We've also touched on the idea of a leaf litter/botanical bed as "nursery" for fry, something I recently discovered in a conversation with noted breeder Rachel O'Leary that she has embraced for years with much success! This, of course, freaked me out in a very good way! 

So, yes, beyond the simple aesthetics, enriching or composing a substrate entirely with botanicals and leaves gives the hobbyist the prospect of success on a variety of fronts!

More to explore...To be continued.

Stay curious. Stay skeptical. Stay diligent. Stay observant...

And Stay Wet.


Scott Fellman

Tannin Aquatics