Rain, botanicals, and the "365 Dynamic..."

As a lifelong resident of Los Angeles, when it reads here, for some reason, it becomes that biggest news around. You'll literally have people calling in radio stations, breathlessly exclaiming, "And there's just like tons of rain coming down here in Santa Monica!" (or insert your fave L.A. suburb). We freak out about it. Avoid driving in it, and generally celebrate it.

And that's how it should be, IMHO!

It's transformational, essential for our existence...and for the continued existence of many of the fishes we love, as well as the habitats from which they come.

(Pic by David Sobry)

And specifically, what interests me about rain is what happens when it rains in the wild habitats of our fishes, and how they behave. How do their habitats change with the coming and going of the rains?  What happens to the fishes during the rainy season?

I know, you're gonna say, "They get wet..." 

Look, no one likes a smartass, okay? 😆 Especially a fellow smartass!

Well, what happens in the "rainy season" in say, the Amazon Basin? (like, why did you know that I'd start there? Hmm?)

A lot of things, really.

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?

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 "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 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 busy work.

Think about 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 a  biotope 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.

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

And utilizing botanicals is just the start, really. 

Yes, you'd have to make some provisions for "relocating" the terrestrial inhabitants of your system, like frogs, to "higher ground" (i.e.; another vivarium) during the "wet season"...or your could create a paludarium-type setup, with both a terrestrial and an aquatic component simultaneously, and not sweat it.

The possibilities for education, creative expression, and flat-out experimentation are really wide open here. A great way to examine and appreciate the cycle of life for many organisms!

Hey, wouldn't this be a cool way to play with some  annual or bottom-spawning killifishes?  Yeah! 

It's just another example of looking at Nature, then thinking of ways to really incorporate her function into our aquatic displays. 

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 manages 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!

We also happen to like the way it looks, of course! 

Let's get to it.

Right now, however, I'm just gonna look out the window and enjoy the rain for a bit. Did I mention, it's raining here in L.A., and...

Stay inspired. Stay intrigued. Stay curious...

And Stay Wet.


Scott Fellman

Tannin Aquatics 

Scott Fellman
Scott Fellman


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