What vital functions do ostracods perform in an aquarium or pond?

Ostracods are unknown in traditional fishkeeping.

Yet, they are among the most widespread animals in the micro-fauna of all aquatic environments on the globe.
Absolutely all. Marine or freshwater.

The number of ostracod species is estimated at 20,000, of which 60% are still unknown!

Ostracods have existed since prehistoric times, and their fossils are even used to date certain sediments.

How then to explain that these tiny crustaceans, omnipresent in all aquatic systems on the planet, are unknown in aquariums?

Probably because fishkeeping has long been marked by a technophile culture. Each function being ensured by an electrical device, the aquatic micro-fauna was somewhat scorned, even feared. Every creature appearing in an aquarium caused concern, and the first goal was to find ways to eliminate it.

Yet, ostracods are certainly the class of creatures that fulfill the most different functions in bodies of water.

They are mostly detritivores and break down all organic waste, plant or animal: dead leaves, various carcasses, sick plants, etc. Even the fine plankton fallen to the bottom feeds them!

Unlike daphnia, which filter only suspended elements in the water.

Thus, ostracods swim, gallop, and walk on supports or the bottom, searching for anything lying around! They are the ones who eat the molts of daphnia and water lice, and who make the contents of a dead snail disappear before it pollutes the water...

Not very appetizing for fish, they are often ignored for some time, especially if the fish are used to better food. In that case, the fish will only take interest in them in times of scarcity.

In natural aquariums, without filters, they are not at risk of being sucked in. But they can also be placed in a sump so they can work sheltered from the fish.

But above all, in aquariums with creatures and without fish, one spends wonderful hours, with or without a magnifying glass, watching them gather by the dozens to lay eggs (not everything is known about their reproduction), wriggling on a small dead fragment, like the minions from the film, to which they actually bear a strong resemblance!

If you have decided to take up natural fishkeeping or fishless aquariums, these amazing little creatures will be an essential base of your ecosystem.

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