January 13, 2016

Reading the (Catappa) Leaves...

If you're a hobbyists who enjoys studying the environments that your fishes originate from as much as you enjoy studying the fishes themselves, then you're probably already a fan of creating aquariums around fishes that live in a certain niche in nature, or around certain habits that they embrace. Called a "biotope aquarium" such a display is a cool and very educational way to keep tropical fishes, and we're excited to offer materials to help you create such memorable aquatic displays.

It's remarkable just how many diverse species of fishes inhabit aquatic systems in nature which are dominated by leaves and submerged terrestrial plant materials, such as seed pods, branches, and roots. Here are a couple of interesting types of fishes we've been obsessed with recently which come from such an environment!

Parananochromis is a beautiful and interesting cichlid genus native to tropical West Africa. Only comprised of eight species, it’s relatively new to science, and really quite rare in the trade. Many of the fish in this genus come from waters that are remarkably acidic, sometimes as low as pH 5.0 or less, and a general hardness of 0! They contain tremendous amounts of decaying leaf litter, seeds, pods, submerged branches, and other botanical materials.

What does this tell us about how we can maintain these interesting fishes in the aquarium?

Well, for one thing, it tells us that they probably do best in an environment with plenty of areas to retreat to when threatened or otherwise disturbed. It also tells us that, in addition to the protection they enjoy from the layer of leaves and such, they probably derive other befits, such as nutrition and spawning substrates within the matrix of these materials.

Another cool genus of cichlids which tends to forage in leaf litter-infused waters is Congochromis. We don’t seem to see these guys as often as we’d like, but they have beautiful colors and fascinating behaviors.

(Pic by Udo Vorhusen Licensed Under CC BY-SA 3.0)

Coming as they do from rainforest streams, you’d expect them to be found in areas that have a soft substrate, littered with lot of decomposing plant material, including leaf litter, twigs and other debris. The key takeaway here again is leaf litter. Like, these fishes come from pretty deep leaf litter areas!

Hmm...

This of course gives us a neat clue as to the type of environment that they might be best kept in captivity. As a fan of leaves and other aquatic botanicals, I’m very interested in the possibilities that they offer to maintain and breed fishes from leaf litter zones in captivity. One of the reasons they are not so easy to collect in the wild is that they may bury themselves deep into the substrate of leaves to escape predation!

Those leaves again.

In addition to providing a chemical and physical environment that is suitable for these species, the leaf litter may also also provide for the production of protozoa, which is beneficial as a supplemental food source for newly hatched fry.

It’s a common theme in many tropical fishes come from rivers and streams…They use leaf litter as not only a place to hide, reproduced, and live…they derive some of their sustenance from these very leaves as they decompose, hosting a tremendous amount of life forms, from copepods to insect, in which they feed. So, you could probably say that these fishes are benthic detritivores, feeding on plant materials and organic detritus, in which aquatic insects and invertebrates are consumed, too.

(Pic by Frank Fox Licensed under CC BY-SA 3.0)

Of course, the leaves themselves, as they decompose, enrich the substrate and overall aquatic environment with minerals, trace elements, tannins, and other substances which benefit the animals which inhabit this niche.

In the aquarium, when the leaves and other botanicals we keep break down, they're performing many of the same functions as they do in nature. Granted, in the closed environment of the aquarium, there are aesthetic and maintenance considerations (like stability of water chemistry) to contend with. You'll have to keep an eye on things; leaf litter biotope aquarium are certainly not "set and forget" systems. Whether you choose to remove some or all of the materials as they break down is purely your choice.

If you're diligent on monitoring and maintaining water quality in your aquaria, there is no reason why you can't use the benefits of leaves and botanicals to your advantage, helping to provide a more complete, more natural-looking, more "functional" biotope aquarium for your fishes from specialized environmental niches.

We offer the materials- Mother Nature offers the inspiration.

Go out there and research, replicate, and enjoy!

And most of all..

Stay wet!

Scott Fellman

Tannin Aquatics