Keyhole Angelfish

The Keyhole Angelfish is one of the largest members of the Centropyge genus, reaching up to 7 inches in length. It is characterized by its predominantly black body adorned with a distinctive white vertical marking on the upper flank that resembles a keyhole, giving this species its common name. Juveniles may display additional blue highlights on the fins that fade as the fish matures into its more somber adult coloration.

Widely distributed across the Indo-Pacific from East Africa to the Western Pacific, the Keyhole Angelfish is found on coral reefs, lagoons, and rocky slopes at varying depths. Despite its wide range and relative abundance, it is not as commonly seen in the aquarium trade as some of its more colorful relatives. In the wild, it is an active grazer that feeds on algae, sponges, and small invertebrates growing on reef surfaces.

In captivity, the Keyhole Angelfish is moderately hardy and adapts well to established marine aquariums. Its larger size compared to most dwarf angelfish means it requires a minimum tank size of 75 gallons. This species can be more aggressive than smaller Centropyge species and has a higher propensity for nipping at corals, making it a riskier choice for reef aquariums. It is best suited for fish-only or fish-only-with-live-rock setups, though some aquarists do keep them successfully in reef tanks with close monitoring.