Emperor Angelfish

General information

Has a bold, blue body covered with bright yellow horizontal stripes culminating in a bright yellow to orange caudal fin. A striking blue-black mask covers the eyes and a similarly-colored vertical band extends from the pectoral fin two-thirds of the way up the body. This band is highlighted in a sapphire-blue in front, and bright yellow, caudally. The mouth is white. The juvenile is black with circular white and blue stripes starting at the tail. Although sought after for its colors, in captivity, the adult coloration may not be as striking or brilliant. The changing angelfish will vary in coloration and pattern as it transforms from juvenile to the adult coloration.

Emperor angelfish are omnivorous, feeding mainly on sponges, tunicates, and algae. It also feeds on other encrusting organism such as hydroids and bryozoans. In tank conditions, it is best if the prepared food contains sponge and tunicate materials with additional meaty food like mussels, shrimp, squid, and spinach.

Sexual orientation of the emperor angelfish can be distinguished based on their sizes and coloration. Male individuals tend to be larger and have a darker blue anterior to and below the eye bar, female individuals are smaller and have a more muted color (light blue-grey).

Breeding in home tanks has not yet been done for the Emperor Angelfish, however it is possible to breed and raise this species in larger tanks.
Courtship for this species usually occurs at dusk, this then progresses to an ascent to the water column by the males followed by females which eventually lead to the release of gametes in the water column for external fertilization. During courtship the male will trail behind the female positioning his snout to near the female's abdomen.

Prone to White Spot Disease and Velvet Disease which causes blotchy coloration on the dark skin areas. It is also prone to Head an Lateral Line Erosion (HLLE) which causes a disfigurement on the fish.

It is widely distributed in the Indo-Pacific region with the exception of the Easter Island, Rapa and the Marquesan Islands. It ranges from the Red Sea and East Africa to the Hawaiian, Line and Tuamoto islands, north to southern Japan and the Ogasawara Islands, south to the Great Barrier Reef, New Caledonia, and the Austral Islands.

When threatened, the Emeperor fish may make grunting noises and turn on its side and hover horizontally just above the bottom. They are semi-aggressive but can be aggressive to other angelfish that are of the same shape, size, and feeding habit.
Always introduce a juvenile Emperor Angelfish as the last fish to the tank to prevent any territorial behavior.

It needs a stable and mature environment, at least 6 months old, with a minimum of 125 gallons.