Naso annulatus

Identification	Large, elongated gray body. Adults develop a prominent rostral horn and elongated tail filaments. The tail fin has white margins on the upper and lower lobes.
Maximum Length	Up to 39 inches (100 cm) — one of the largest surgeonfish
Origin	Indo-Pacific — East Africa to Hawaii
Minimum Tank Size	300+ gallons
Reef Compatible	Yes

Behavior

An impressive, open-water species that may be the largest surgeonfish in the hobby. Peaceful despite its size and rarely bothers corals or invertebrates. Requires enormous space and very high water quality. Best reserved for large-scale systems.

Diet & Feeding

Feeds on leafy macroalgae, gelatinous zooplankton, and some small organisms. Offer dried seaweed, marine algae, and frozen meaty foods. This species has a very large appetite.

Cautions

Appropriate only for very large public or private aquariums. Adult specimens cannot be kept in standard home systems. Research adult size before purchasing.