Queen Angelfish

The queen angelfish is one of the iconic fish of Caribbean reefs. Each scale on its blue–green body is edged in yellow; the tail and pectoral fins are bright yellow, and the tips of the dorsal and anal fins are long and edged in blue. It takes its name from the dark "crown" spot ringed in blue on its forehead. Juveniles carry light blue vertical lines and yellow areas on a dark blue background; the change happens gradually as they grow.

All individuals are collected from the wild. In the wild it hybridizes with its close relative, the blue angelfish (Holacanthus bermudensis); these hybrids are known in the hobby as the "Townsend angelfish."

It lives on shallow reefs, rocky areas and sponge gardens of the western Atlantic. In the wild, sponges make up most of its diet; it also eats algae, tunicates and coral polyps. Juveniles are known to clean parasites off other fish in the wild.

• Volume: at least 1000 liters and 200 cm in length for an adult; enough width to turn around and open swimming space.
• Water: salinity 1.023–1.026 specific gravity, pH 8.1–8.4, temperature 24–27°C. Strong filtration and a protein skimmer for the large bioload.
• Decor: a solid rock layout with caves and passages.
• Maintenance: a 10–15% water change weekly; nitrate should be kept below 20 mg/l. In large angelfish, high nitrate is linked to fading color and HLLE.
• Reef compatibility: not reef safe. It eats soft and LPS corals, zoanthids, tridacna clams and sponges. Suitable for a fish-focused (FOWLR) aquarium.

Omnivorous. Angelfish foods containing sponge should be the staple; frozen mysis, chopped mussels, squid and shrimp, spirulina and dried seaweed should be added to these. Feed 2–3 times a day.

Adults are bold and territorial. They attack their own species, other large angelfish and similar fish added later. Given enough space, it gets along with other large fish.

Good companions: in a very large aquarium: tangs, large wrasses, Heniochus, foxface, calm triggerfish, large porcupinefish.

Avoid: other large angelfish, reefs with corals and tridacna clams, small and timid fish.

Kept as a single individual in the aquarium. In the wild it forms pairs or small harems; this arrangement cannot be provided in a home aquarium.

Pairs rise into the water column in the late afternoon and release pelagic eggs. It does not breed in home aquariums.

• Head and lateral line erosion (HLLE): common in large angelfish; a varied diet and clean water prevent it.
• Marine white spot and velvet: quarantine is essential.
• Poor nutrition: on a monotonous diet without sponge, the colors fade and the fish loses weight.

The sexes cannot be reliably told apart externally.