Moorish Idol

Zanclus cornutus

Identification	Unmistakable disc-shaped body with bold black, white, and yellow vertical bands. An extremely long, trailing white dorsal filament extends from the dorsal fin. The snout is long and tubular.
Maximum Length	Up to 9 inches (23 cm)
Origin	Indo-Pacific and Eastern Pacific — one of the most widely distributed reef fish
Minimum Tank Size	100 gallons
Reef Compatible	Generally yes — does not harm corals, but grazes on sponges

Behavior

One of the most iconic and recognizable reef fish, the Moorish Idol is notoriously difficult to keep in captivity despite its common appearance on wild reefs. Its highly specialized diet and sensitivity to stress make it a challenge even for experienced hobbyists. Only attempt if you can provide a very mature, nutrient-rich reef system.

Diet & Feeding

Spongivore. In the wild feeds almost exclusively on sponges. Captive specimens must be weaned onto sponge-based prepared foods, live sponge material, and supplemented with frozen mysis and enriched brine shrimp. Many captive specimens slowly starve without live sponge sources.

Cautions

Considered an expert-only fish. High mortality rate in captivity due to dietary needs. Do not purchase unless you have a well-established system with ample sponge growth and experience with difficult feeders.