Pennant Coralfish / Longfin Bannerfish

Geographical Origin and Habitat: Widespread in the Indo-Pacific, from East Africa and the Red Sea to French Polynesia, north to Japan, and south to Australia. Inhabits deep lagoons and outer reef slopes down to 75 meters.

Taxonomy and Morphology: Member of the family Chaetodontidae. Features a deep, laterally compressed body, with an extremely long white pennant extending from the fourth dorsal spine. Reaches up to 25 cm (10 inches).

Social Behavior: Peaceful and social. Juveniles school in large groups, while adults are typically found in pairs or small shoals. Active open-water swimmer.

Coloration and Sexual Dimorphism: Body displays broad alternating black and white vertical bands. The soft dorsal fin, caudal fin, and pectoral fins are bright sulfur-yellow. No visible sexual dimorphism.

Aquarium Setup: Requires a large aquarium of at least 350 liters to allow ample room for active swimming. Provide some live rock structures but keep the center open.

Diet and Feeding: Omnivorous. Readily accepts mysis, brine shrimp, chopped krill, commercial flakes, pellets, and marine algae. Feed twice daily.

Water Quality: Considerably hardier than most butterflyfish. Ideal parameters: temperature 24-27°C (75-81°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 caution; may nip at fleshy LPS corals, zoanthids, or clam mantles if underfed. Excellent tankmate for non-aggressive community fish.

Aquarium Breeding: Highly difficult. Pelagic spawners releasing eggs into the water column. Unrecorded breeding in home aquariums.

Risks and Diseases: Prone to external parasites such as marine ich and velvet if subjected to poor shipping conditions or sudden water changes.