Emperor Angelfish Pomacanthus imperator
The Emperor Angelfish is native to reefs of the Indian and Pacific Oceans.
Adults, with their attractive bright yellow and blue body lines and white face with purple-edged bandit mask,
reach some 40 cm long.
They usually form pairs. When frightened, they can make a knocking sound.
Diet is variable but they particularly eat algae, sponges and tunicates.
Juveniles (not shown) look very different with a dark blue background and white, circular and semi-circular lines.
Both juveniles and even adults have been known to work as cleaner fish to larger fish species.