Angelfish belong to the order Perciformes, and marine angelfish in particular belong in the Pomacanthidae family. There are at least 7 genera and 86 species of marine angelfish in this family. Freshwater angelfish belong in the same order, but in the Cichlidae family instead. Freshwater angelfish are found in South America in places like the Amazon River Basin. Marine angelfish only live in saltwater, no freshwater or brackish water. They are found on shallow reefs in the Atlantic, Indian, and Western Pacific Oceans, but mostly in the Western Pacific. Most angelfish live in the shallows of a reef above 50 meters, though the Centropyge abei has been reported to inhabit waters at a depth of 150 meters. They will hide during the day in reef and rock crevices. Angelfish may be solitary, or found in mating pairs or groups. If it is a group, it will usually consist of one male and several females.
Despite how robust and eye-catching the colors of an angelfish can be, these patterns actually help the fish camouflage among the shadows of the reef. Saltwater angelfish can live to be up to 15 years old, and they’re one kind of fish species where the juvenile’s colors and patterns change drastically as they become an adult. All marine angelfish have a laterally compressed body like a flat disc, and prominent spines on their gills. The fins of marine angelfish are more round and crescent-shaped, as opposed to the triangular fins of freshwater angelfish. Angelfish are grazers that feed off of sponge and tunicates, but they do also consume smaller fish and crustaceans. If left unchecked, a population of angelfish could become destructive to the reef. Young angelfish are consumed by many different species, including birds, while adult Angelfish are primarily a food source for sharks, marine mammals, and humans. Angelfish are pelagic spawners, so the eggs they release float in the water column alongside plankton species that may unfortunately be consumed by planktivores and omnivores alike.
Small angelfish are more desirable for aquarium fish. The larger, often more aggressive, species require being placed in a tank with other fish equally as aggressive. In the wild, these angelfish can be very bold and swim close by to snorkelers and divers alike. This trait, coupled with their brighter more exotic colors, make angelfish one of the more conspicuous species on the reef for swimmers to spot. A few angelfish that are considered threatened face greater mortality rates due to exposure to cyanide. Cyanide is unfortunately used by some collectors when capturing fish species. Otherwise, not many angelfish hold the threatened status. More often, angelfish are considered to be a threat themselves for coral reef habitats if population numbers are too high.