Schooling fish

[Chin_Lee]

I haven't been able to find a type of find that stays schooling after extended period of time in a hobby tank. The natural instinct for fish to school is for protection. When you introduce the school of fish into your tank, it will school because it feels threatened. After a period of time when they no longer feel threatened by your presence, they will stop schooling and often display aggression towards each other. Chromis is one such fish that I've had that will pick on the weakest in the school until one or two remain.