Royal Dottyback

Geographical Origin and Habitat: Broadly distributed in the Western tropical Pacific, from Indonesia and the Philippines to the Solomon Islands and the Great Barrier Reef. Inhabits drop-offs and coral slopes with abundant crevices at depths of 2 to 80 meters.

Taxonomy and Morphology: Member of the family Pseudochromidae. Features an elongated, compressed body reaching a maximum size of 7 cm (2.8 inches). Expressive eyes with tear-shaped pupils.

Social Behavior: Highly aggressive and territorial. Vigorously defends its chosen rocky cave and patrols the tank, chasing away any fish that approaches its territory.

Coloration and Sexual Dimorphism: Spectacular, sharp bi-color pattern: the front half of the head and body is brilliant magenta-purple, while the rear half and tail are bright golden yellow. No visible sexual dimorphism.

Aquarium Setup: Needs at least 120 liters of tank volume with extensive live rock arranged to create numerous tiny caves and tight crevices. A tight-fitting lid is required as they are active jumpers.

Diet and Feeding: Carnivorous. Eagerly consumes frozen mysis, brine shrimp, chopped krill, and high-quality pellets. Highly beneficial as a biological control for pest bristleworms and flatworms.

Water Quality: Exceptionally hardy and tolerant of poor water quality. Ideal ranges: temperature 24-26°C (75-79°F), pH 8.1-8.4, specific gravity 1.020-1.025, GH 15-25, and KH 8-12.

Compatibility and Cohabitation: Reef-safe with corals. However, it will aggressively harass peaceful, passive, or similarly colored tankmates (like the Royal Gramma). Best housed with robust tankmates and introduced last.

Aquarium Breeding: Possible. The male courts the female into a cave where she deposits a ball of adhesive eggs. The male guards and aerates the nest until hatching.

Risks and Diseases: Very disease-resistant. The main risk is severe territorial aggression, often resulting in the death of shyer tankmates.