Juvenile emperor angelfish have been found cleaning larger fish.
Emperor angelfish hide in caves and under ledges. They stay near reefs and surge channels where they can escape predators easily. They are native to the Indo-Pacific Ocean and can be found from the East Africa all the way to the Hawaiian Islands.
Obviously an emperor
Adult emperor angelfish are some of the most recognizable fish in aquariums. Their bodies have yellow and blue horizontal stripes that stretch from behind the gills to the tail, which is yellow. Young emperors are dark blue with three thick white bands mixed with black vertical lines. Many people confuse juvenile Koran angelfish with juvenile emperor angelfish. The biggest identifier is that the last white stripe on the Koran juvenile doesn’t create a complete circle, while it does for the emperor. Emperor juveniles have unusual blue lines and circles on their dorsal and anal fins. Korans don’t have them.
In the wild, most emperor angelfish swim alone. Occasionally, a male with one or two females or a juvenile will be spotted together, but rarely with another mature adult male. Emperor angelfish are aggressive and territorial on the reefs, especially towards smaller fish like clownfish. In captivity, emperors are more peaceful.