Colorful species of saltwater and freshwater fish include lion fish, Siamese fighting fish, Moorish idols and fantail guppies. Many of these species are available for home aquariums, though some of them have special needs and are not recommended for beginning hobbyists.
Fish coloration is not just for beauty, it also serves a practical purpose. Coloration provides camouflage, acts as a warning or can attract a mate. Stripes and spots help break up a fish's outline or mimic the patterns of a more dangerous species. Bright colors, such as those of the lion fish, warn predators of poisonous spines, venom or extreme aggressiveness.