June 29, 2018

In the shallows of streams...

It's no secret that we love small aquariums around here. For a lot of reasons, really...not the least of which is that they can serve as a sort of reliable and easy-to-iterate "test bed" for lots of new ideas.

You're also likely aware of the fact that we're crazy about small, shallow bodies of water, right?

Especially little rivulets, pools, creeks, and forest streams. The kinds which have an accusation of leaves and botanical materials on the bottom.

You know, the kind where you'll find fishes!

Happily, such habitats exist all over the world, leaving us no shortage of inspiring places to attempt to replicate

In Africa. many of these little streams and pools are home to some of my fave fishes, killifish!

As mentioned above, these little jungle streams are really shallow, cutting gently through accumulations of leaves and forest debris. Many are seasonal. The great killie documenter/collector, Col. Jorgen Scheel, precisely described the water conditions found in their habitat as "...rather hot, shallow, usually stagnant & probably soft & acid."

Ah-ah! We know this territory pretty well, right?

I think we do...and understanding this type of habitat has lots of implications for creating very cool biotope-inspired aquariums. And why not make 'em for killifish?

So, for the most part, these fishes are often found in very shallow jungle streams. How shallow? Well, reports I've seen have stated that they're as shallow as 2 inches (5.08cm). That's really shallow. Seriously shallow! And, quite frankly, I'd call that more of a "rivulet" than a stream! "Virtually still, with a barely perceptible current..." was one description. That kind of makes my case.

What does that mean for those of us who keep small aquariums?

Well, it gives us some inspiration, huh? Ideas for tanks that attempt to replicate and study these compelling shallow environments...

Now, I don't expect you to set up a tank with a water level that's 2 inches deep..And it would be pretty cool...For more of us, perhaps a 3.5"-4" (8.89-10.16cm) deep depth is something that can work? Totally doable. There are some pretty small commercial aquariums that aren't much deeper than 8" (20.32cm), and you could adapt other containers for this purpose, right?

We could do this with some of the very interesting South American or Asian habitats, too...Shallow tanks, deep leaf litter, and even some botanicals for good measure.

How about a long, low aquarium, like the ADA "Cube Garden 60F", which has dimensions of 24"x12"x7" (60x30x18cm)? You would only fill this tank to a depth of around 5 inches ( 12.7cm) at the most. But you'd use a lot of leaves to cover the bottom...

And another idea for you...Nano brackish tanks!

Here is a pic of my experimental brackish water Epiplatys annulatus setup from several years back. (Yes, there are actually some populations which come from brackish coastal streams! ohhhh!) This one I actually filled to the top, used a fine layer of fine, white sand, and kept the water at a specific gravity of 1.003. It was kind of an odd dichotomy, really, because I used some botanical items in the sort of "island" of rock I created in the lower light area on one side.

You can guess where the fish spent most of their time! I incorporated what I now call "Mariposa Pods" a few little "Savu Pods", and some Coco Curls into the "island", which had a mix of terrestrial and true aquatic plants, with slightly different water. I guess you could say that it was kind of my first attempt at a botanical-style brackish water aquarium! Not exactly an aquascaping triumph, but an execution on an idea that was in my head for a long time.

(Yeah, I've always liked pushing in different directions!)

You could, of course, do a far more refined version of this early experiment, one with mangroves and leaf litter and mud- all of the elements we've talked about, but in a small scale.

Yes, this is another blog where I'm sort of all over the place; must be the early pre-coffee start.

The big takeaway here?

Research jungle stream or pool ecology. Learn which fishes are found in them. Try replicating those super-shallow aquatic environments with nano tanks. Keep the water in the tank shallow. Add leaves and stuff. Observe. Explore. Enjoy.

Stay excited. Stay curious. Stay creative. Stay engaged...

And Stay Wet.

Scott Fellman

Tannin Aquatics