The dynamics of botanical-style aquariums

 Botanical-style aquariums are a bit different. Yet, they're not THAT different from aquarium systems we've become more accustomed to over the years, right?


Our botanical-style aquariums are not "set-and-forget" systems, and require consistent basic maintenance (water exchanges, regular water testing, filter media replacement/cleaning), like any other aquarium.

They're truly dynamic.

We have developed some regular practices in the botanical-style aquarium hobby.  Perhaps one of the most "time-honored" practices is the idea of replacing decomposing materials with new ones regularly. This is one unique "requirement" as part of their ongoing maintenance which differs botanical-style aquariums from other types of aquariums.

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.

Because not only does Nature evolve our tanks by decomposing botanical materials over time, but we as hobbyists take part in this process by replenishing them with fresh materials.

Botanicals should be viewed as "consumables" in our hobby- much like activated carbon, filter pads, etc.- they simply don't last indefinitely.

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. The side benefits are immediately apparent, too: 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.

Over the years, I've found 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 that Nature has done for eons; something very "primal" and essential. Even the preparation process is engaging.

When you think about the materials which accumulate in natural aquatic habitats, and how they actually end up in them, it makes you think about this in a very different context. A more "holistic" context that can make your experience that much more rewarding.

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 flooded forests (igarape) and streams of the region!

I have an obsession for small little tropical streams; their evolution, form, and function.They are remarkable little habitats, with literally thousands of different fishes found residing in them. 

The definition of a "stream" is: "...a body of water flowing in a channel or watercourse, as a river, rivulet, or brook..."

And of course, these little bodies of water flow through jungled areas, where they're bound to pick up some leaves, twigs, and other plant parts as they wind along their path. Leaves, the "jumping off point" of our botanical obsession, form a very important part of these stream habitats.

It is known by science that the leaf litter and the community of aquatic animals that it hosts is, according to one study, "... of great importance in assimilating energy from forest primary production into the blackwater aquatic system." 

There is something that calls to me- beckons me- to explore, to take note of its intricate details- and to replicate some of its features in an aquarium- sometimes literally, or sometimes, simply taking components that I find compelling and utilizing them in my tanks.

Streams also function as a means to preserve the nutrients that would be lost to the forests which would inevitably occur if all the material which fell into the streams was simply washed downstream. The fishes, crustaceans, and insects that live in the leaf litter and feed on the fungi, detritus, and decomposing leaves themselves are very important to the overall habitat.

In this world of decomposing leaves, submerged logs, twigs, and seed pods, there is a surprising diversity of life forms which call this milieu home. And each one of these organisms has managed to eke out an existence and thrive. 

A lot of hobbyists not familiar with our aesthetic tastes will ask what the fascination is with throwing palm fronds and seed pods into our tanks, and I tell them that it's a direct inspiration from nature! Sure, the look is quite different than what has been proffered as "natural" in recent years- but I'd guarantee that, if you donned a snorkel and waded into one of these habitats, you'd understand exactly what we are trying to represent in our aquariums in seconds!

Of course, water chemistry of flooded forests and streams is influenced by the many terrestrial components of the habitat. The trees in the ecosystem enrich the habitat and the resulting organic detritus from decomposing bark and organic exudates from the trees themselves help concentrate nutrients within the ecosystem itself.

Learning more about the dynamics of stream habitats and the ecology of the surrounding terrestrial environments is just one fascinating and compelling area of study that we as aquarists can really get into.

Yes, it requires some study. It requires trying some new and seemingly wacky ideas (encouraging the accumulation of detritus, decomposing leaves, and epiphytic biofilm growth, for one thing!), and embracing some different aesthetics in our aquariums.

Let's focus on this "functional" dynamic for a second. When we look to Nature, it's increasingly obvious that we can replicate much of it in our aquariums.This quote from a paper by Mendonca, et al, tells me so many cool things about the habitats we love to replicate:

"In Central Amazonia, terra firme environments (uplands that are not seasonally flooded) are drained by streams that have acidic waters due to the presence of humic and fulvic acids. The waters are poor in nutrients and the forest canopy impairs light penetration to the stream surface, so aquatic plants are virtually nonexistent (Junk and Furch, 1985; Walker, 1995). In these oligotrophic environments, food chains are dependent on allochthonous material from the forest, such as pollen, flowers, fruits, leaves, and arthropods (Goulding, 1980; Goulding et al., 1988; Walker, 1991). However, small fishes are frequently abundant, and 20 to 50 species may occur in a single stream (Lowe-McConnell, 1999; Sabino, 1999)."

In streams, studies indicate that an increase in species "richness" is positively related to the habitat complexity and shelter availability as well as current velocity and stream size, and that substrate, depth and current speed are among the most important physical features in many bodies of water, which contribute to the formation of numerous "microhabitats", all with fascinating ecology, environmental parameters, and fish population diversity.

 Stuff we've barely tapped into in the aquarium world yet!

The implications of this information for aquarists are profound and fascinating, and understanding, interpreting, and applying some of these numbers and concepts can potentially lead to some fascinating breakthroughs in aquarium work.

However, we have to "get out of our own way", first.

We're talking about taking the lead from Nature- looking at it as it IS- and about using this stuff to create aesthetically compelling, dynamic, and physically functional aquariums. There is always the danger of going too far, and falling into that cliche of closed-minded superficial replication that is, in my opinion, consuming the aquascaping and biotope aquarium world, so use the information you find with a bit of interpretation...but make use of it nonetheless.

It's time to create awesome-looking aquariums that also function like the natural habitat which they intend to replicate.


They may not be "pretty" in the conventional aquarium sense. 

They might not look or function like a "traditional aquarium", and they might not be attractive to many in the same way a more "high concept" planted tank is...And that's okay. It's important to understand that we're going in a different, very unique direction- one which has a different goal, and will, with a different operational approach- yield a very different outcome.

All of these things are very interesting, and so much is yet to be learned and experienced by us as hobbyists in relation to leaf litter and botanicals in our aquariums. Yet, one can only hope that many of the positives which occur in natural habitats comprised of leaf litter and botanical cover will occur in our thoughtfully-managed aquariums.

The day will come when we have a better understanding of what's really going on in leaf litter beds in our tanks, and that these materials won't be coveted just for their ability to impart tannins and humic substances, or for creating a different aesthetic, or for lowering pH and tinting the water, but for the true biological "richness", diversity, and utility they provide.

I celebrate our effort to understand, execute, and embrace the dynamic processes which occur within them, and allowing all of the life forms which reside within them to benefit from them.

Stay engaged. Stay bold. Stay diligent. Stay patient. Stay studious...

And Stay Wet.


Scott Fellman

Tannin Aquatics 


Scott Fellman
Scott Fellman


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