The dynamics of the botanical-style aquarium...

The most interesting thing about botanical-style aquariums, particularly from the perspective of an aquascaper, is that they are not "static" systems. In other words, almost from the minute you set them up, they begin changing..."evolving", as our community likes to say. Not unlike planted aquariums in some respects, purely botanical-style systems are highly dynamic, and look slightly different each and every day.

Oh sure, the "permanent" hardscape- the wood, the rocks (if you use them) are not going anywhere; typically, not changing much, with the exception of "recruiting" biofilms and perhaps a "patina" of algae over time. However, by-and-large, the rest of the 'scape- leaves, seed pods, twigs, etc., starts to soften, break down, recruit biofilms, and are moved about by current and the activities of resident fishes.

Our botanical-style aquariums are not "set-and-forget" systems, and require basic maintenance (water exchanges, regular water testing, filter media replacement/cleaning), like any other aquarium.  They do have one unique "requirement" as part of their ongoing maintenance which other types of aquariums seem to not have: The "topping off" of botanicals as they break down.

It's a regular thing; almost a revered, ritualistic sort of thing among us hardcore botanical-style aquarium freaks.

The "topping off" of botanicals in your tank accomplishes a number of things: first, it creates a certain degree of environmental continuity- keeping things consistent from a "botanical capacity" standpoint. Over time, you have the opportunity to establish a "baseline" of water parameters, knowing how many of what to add to keep things more-or-less consistent, which could make the regular "topping off" of botanicals a bit more of a "science" in addition to an "art."

In addition, it keeps a consistent aesthetic "vibe" in your aquarium. Consistent, in that you can keep the sort of "look" you have, while making subtle- or even less-than-subtle "enhancements" as desired. 

Yeah, dynamic.

And, of course, "topping off" botanicals helps keeps you more intimately "in touch" with your aquarium, much in the same way a planted tank enthusiast would by trimming plants, or a reefer while making frags. When you're actively involved in the "operation" of your aquarium, you simply notice more. You can also learn more; appreciate the subtle, yet obvious changes which arise on an almost daily basis in our botanical-style aquariums.

I dare say that one of the things I enjoy doing most with my blackwater, botanical-style aquariums (besides just observing them, of course) is to "top off" the botanical supply from time to time. I feel that it not only gives me a sense of "actively participating" in the aquarium- it provides a sense that you're doing something nature has done for eons; something very "primal" and essential. Even the prep process is engaging.

Think about the materials which accumulate in natural aquatic habitats, and how they actually end up in them, and it makes you think about this in a very different context. A more "holistic" context that can make your experience that much more rewarding. Botanicals should be viewed as "consumables" in our hobby- much like activated carbon, filter pads, etc.- they simply don't last indefinitely.

Nature does it's own version of this "topping-off" process, too, of course!

Many bodies of water which meander through jungles and rain forests are constantly being "restocked" with leaves, seed pods, branches, and other botanical materials from the surrounding vegetation- some of which are knocked into the water by weather, wind, animal activity, etc. Depending upon the velocity of the water, its depth, etc., they may aggregate right where they fall, or be gradually re-distributed downstream by the current.

Interestingly, in places like the rain forest streams of Amazonia, biologists have observed floating leaf litter beds which hold together for quite a long time- almost becoming known "features" in the aquatic "topography" of the igarapes and streams of the region!

So imagine, if you will, a "classic" submerged leaf litter bed in Amazonia, composed of a variety of leaves, branches, twigs, seed pods, and other botanical materials...Yet, floating on the water surface; extending as much as a few feet under the water! What you get is a fairly deep layer of plant materials colonized by fishes and other creatures, which forage on the macro invertebrate life found in these complex assemblages.

Biologists call this an "ephemeral" habitat, as it is transitory or temporary as it slowly breaks apart-despite the fact that it might be years before this occurs.

Okay, so it slowly breaks apart over months and months.

And often, these floating or partially submerged leaf litter banks either accumulate among the branches of overhanging vegetation during the high-water season, gradually floating downstream, or they stay anchored in place by fallen tree trunks and other large materials, ultimately forming a more "traditional" submerged leaf litter bed as they sink.

Think about the possibilities to replicate them in aquariums!

I found this to be an amazingly interesting niche! Reminds me of the Sargassum "forests" of the Caribbean and Tropical West Atlantic! Literal "floating feasts" for the animals which reside there! This is another potentially irresistible ecological niche for us to play with, right?

Oh- and many fish species associate with these floating litter banks for the entire wet season! 

And one of the reasons they stay put is because their food sources are there, too! In fact, a species of "water bug", Weberiella rhomboides, is found almost exclusively in these floating banks, attracting large numbers of insectivorous fishes, like characins, catfishes, knife fishes, and others. 

Yeah, it's a virtual "who's who" of blackwater, leaf-litter-zone dwellers, some of which are very familiar to us as hobbyists- for example, characins like Hemmigramusspecies, Moenkhausia species, the killifish Rivulus ornatus, and of course, cichlids, including a number of ApistogrammaCrenicichla, Hypselecara, and the much-loved Mesonauta festivus, to name a few. Can you imagine how this could make a very interesting theme for an aquarium?

Yeah, I you'd imagine!

You'd want a fairly shallow, wide aquarium, and probably would filter it with an outside power filter or canister filter with the return positioned in such a way as to minimally disturb the surface. With minimal preparation (ie; cleaning them with a light boil, but not trying to saturate them to the point of the materials sinking right to the bottom), a lot of this stuff would sort of float for a while before sinking to the bottom.

You'd essentially be creating a diverse assemblage of botanicals, just like you would if you were doing a "conventional" leaf-litter display (I love that- I just called this stuff a "conventional leaf litter display"- look how far we've come..WTF.). And of course, Nature offers no shortage of inspiring leaf-litter habitats to examine!

Now, eventually, some of this stuff would sink, or be trapped below the floating "matrix", and you'd end up with materials on the!  It would transition naturally to a more "conventional" botanicals-on-the-bottom display. So this is essentially an "ephemeral display"- transitioning from a "floating leaf litter bed" to a submerged leaf-litter aquarium!

How freakin' cool is that? Of course, you could probably keep it going by replacing the leaves and such as you would anyways, right? And as the wood becomes submerged, you'd "let it do it's thing", and/or replace/add new pieces.

Sure, I digressed a bit...What else is new?

The point is, the wild habitats 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 the phenomenon is not limited to Amazonainan forests, of course. We see the same thing occurring in "mangals"- habitats in which mangroves dominate.

Falling leaves and botanical materials, accumulating, decomposing, and being re-distributed by natural forces is a constant process, helping to enrich the overall habitat for a myriad of organisms. The eco diversity and productivity of mangrove habitats- like many habitats in which leaves and botanical materials accumulate underwater- is remarkable.

I've  seen this phenomenon of leaves dropping naturally (and supplemented by me as well) in my mangrove inspired brackish-water aquarium. In the year or so of operation, I'd see a lot of this type of "evolution" occurring daily. 

Truly a dynamic habitat for fishes. 

Perhaps one of the more completely "functionally aesthetic" aquariums I've built in many years, the brackish tank has really put this function/process "front and center", giving me a "ringside seat" of an evolving brackish microcosm!

Leaves fall, break down, and become a food resource and physical shelter for the fishes and animals which reside in the aquaria, just like in Nature.

And of course, the idea of botanicals accumulating in our aquariums, impacting both the biological diversity and function of them, is a big part about what the excitement of the botanical-style aquarium is all about!

It's not just the unique aesthetics...It's the function that they bring- and the possibilities that accompany them!

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 moved on to "How can I facilitate maximum benefits to my fishes with a blackwater, botanical-style aquarium?"

The point of all of this stuff is that the botanical-style aquariums we love so much are truly dynamic habitats, constantly changing and evolving- much like they do in Nature! The ability to replicate the look, the characteristics, and the function of Nature in our aquariums is an amazing process that will benefit the larger aquarium hobby in ways not even fully realized at this time.


It's a time for more great experimentation. More discovery. And further exploration of the potential of providing our fishes with what might be the most natural simulation of Nature possible.

It's truly an exciting time to be in the hobby- especially in our "sector!"

And, yeah- YOU are right in the thick of it! 

Stay inspired. Stay involved. Stay excited. Stay creative. Stay observant...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

Scott Fellman
Scott Fellman


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