Damselfish are hardy members of the Pomacentridae family. They are marine fish that tend to be aggressive and grow to an average length of 2 inches. 

…healthy aquarium. The first question to be answered, so the tank may be properly set-up, is what fish will be kept in it. 

…certainly one of the most popular of all aquarium fish. Africans are not without their challenges to the aquarist, however. They can be aggressive, predatory, and destructive.