Cardinals for Saltwater Aquariums
Cardinal fish may be small in size, but they can add big interest to any aquarium. When housed in a larger aquarium, cardinals are great fish to use for schooling fish in groups of five or more. However, this is only the case in a large aquarium, as males have a tendency to fight when there is not sufficient space. Cardinals are hardy, but they are a bit shy by nature, so an aquarium with plenty of rock and hiding places is recommended. Some cardinals have been know to exhibit interesting behaviors such as using the spines of an urchin for cover when frightened.