Cynolebias is the biggest Killifish genus and a lot of the species are frequently kept by aquarists. The members of this genus look similar to the African Nothobranchius, only with more delicate fins. African Nothobranchius are typically also more colorful than Cynolebias killifish. The native home for the Cynolebias killifish species is the South American continent. They can be found from Brazil in the north to Argentina in the south.
The recommended water temperature for Cynolebias killifish species is 68-77º F (20-25º C). The native waters are soft and they will therefore prefer soft water in the aquarium. They can however adapt to water that is slightly hard. Very hard water must be avoided. A planted aquarium is recommended for Cynolebias killifish and you should ideally include plant species that provide the fish with a natural cover, e.g. Duckweed. Cynolebias killifish can feel very stressed in a barren aquarium without any hiding spots.
Cynolebias killifish can learn to accept dead food in the aquarium, but live food is recommended. Daphnia, Brine shrimps and different types of worms are all suitable foods. If you do not feed your Cynolebias killifish any live food, their colouration can become dull and listless. Feeding your Cynolebias killifish live food will also make it possible for you to observe a much wider range of natural Cynolebias killifish behaviours. Raising your own Brine shrimp at home is an easy and inexpensive way of providing your Cynolebias killifish with a live diet.
Cynolebias killifish frequently breeds in aquariums. You must however keep in mind that these fishes come from a region affected by seasonal draughts, and their reproductive method is therefore quite advanced. The adult Cynolebias killifish will deposit their eggs deep down in the mud where the eggs survive even if the puddle dries out completely. The adult fish will die during the severe draught, but the eggs will survive until the next rainy season. When the rain returns, the eggs will hatch and the young Cynolebias killifish will soon be ready to spawn before the water dries out once again.
If you want to breed Cynolebias killifish, you must simulate a dry season since the eggs will not hatch without a resting period. Instead of trying to dig up eggs from the substrate of your aquarium, you can provide the adult Cynolebias killifish with a container that they will view as a very nice spawning site. Boil some peat moss, rinse it clean, and place it in a plastic container. The container should have a small opening and be closed with a tight fitting lid. The opening must be large enough for the adult fish to access the spawning site. As you wait for them to spawn, you must change the peat moss every few weeks to prevent bacterial growth. When the eggs have been deposited and fertilized, you can pick up the plastic container and start the “dry season”. The peat moss should be placed in a plastic bag and stored in room temperature 68-77º F (20-25º C). When the “dry season” is over, you simply have to re-hydrate the eggs and they will hatch.