The Rainbowfish is a popular breed, both among beginner and experienced fish keeping enthusiasts. They are small fish, that live well together with other community fish species. Because of their small size, you should avoid putting bigger fish in the same tank as them (Bettas for instance). They are schooling fish, so make sure you have 5 or 6 at least in a group. This way, they will feel at home in their new environment. If you keep multiple ones together, the males will exhibit their best colors towards the females. The group will look much better because of this. Feeding them is pretty simple, since the Rainbowfish are omnivores. You can give them earthworms, pellets, simple vegetables, or specially made food for their kind. However, they are not bottom dwellers, like others on this list. Make sure, they have plenty of space in the aquarium, because they like to swim around in groups. Usually, a 30-gallon tank is enough for a group of 6 Rainbowfish.