Pomacentrus callainusis commonly referred to as Damselfish. Difficulty in the aquarium: There are no reports available yet that this animal has already been kept in captivity successfully. Toxicity: Toxic hazard unknown.
Pomacentrus callainus is found in shallow coral reefs, which it uses for shelter.
The perch displays a light blue-green ground coloration, with the edges of the scales surrounded by a dark margin.
A wedge-shaped black spot on the upper part of the pectoral fins is also conspicuous, the head and chest are dark, and a black spot can be seen at the base of the pectoral fins.
A vertical dark stripe (spot) runs through the eyes of the perch.
The species name "callainus" comes from Latin and means "blue-green" in reference to the coloration of the fish.