Cardinal fishes (Apogon spp) are quite hardy fishes and can be recommended to the beginner as excellent species with which to commence marine fish keeping, apart from the fact that they rarely accept dried food in captivity. Most species have to be fed small live fishes, or after a period in captivity, fresh protein such as minute pieces of earthworm, prawn and steak, etc. These species are mouth-breeders, that is to say that the fertilised eggs are retained in the parent’s mouth for incubation, and so it is possible that cardinal fishes may be among the first species of marine fishes to be successfully bred in captivity.