Allen's Damselfish

Geographical Origin and Habitat: Native to the Western Pacific Ocean, ranging from Java to the reefs of Borneo and southern Japan. Commonly inhabits shallow coral lagoons and sandy areas.

Taxonomy and Morphology: Member of the family Pomacentridae. Features an oval, compressed, and relatively slender body. Reaches a maximum standard length of 6 cm. Smooth scale structure.

Social Behavior: Highly unique for its peaceful temperament compared to other damselfishes. Gregarious species that prefers to live in groups and shoals near rocky shelters.

Coloration and Sexual Dimorphism: Iridescent neon-blue coloration. Displays a prominent horizontal black stripe along the anal fin, and a translucent yellow tail fin. No distinct dimorphism.

Aquarium Setup: Requires a minimum tank size of 80 liters with structured rockwork and coral heads to simulate its natural habitat.

Diet and Feeding: Omnivorous. Provide high-quality small flakes, pellets, frozen daphnia, cyclops, and brine shrimp to maintain health and color.

Water Quality: Standard reef parameters: stable temperature 24-28 °C, pH 8.1-8.4, and salinity 1.020-1.025 with moderate filtration and current.

Compatibility and Cohabitation: Exceptionally peaceful. Highly compatible with reef-safe fishes. Can be kept in a group of 4 or more individuals without aggression.

Aquarium Breeding: Oviparous. Spawns adhesive eggs on rocky surfaces or clean crevices. The male guards and fans the nest until the larvae hatch.

Risks and Diseases: Hardy and active species with low susceptibility to common marine diseases. Good choice for beginner community reef tanks.