Bluespine Unicornfish Care Guide
Naso unicornis is a large Indo-Pacific unicornfish that develops a forehead horn and two blue caudal spines, feeding on coarse brown algae and reaching 70 cm.
Overview
Naso unicornis, the bluespine unicornfish of the family Acanthuridae, has a bluish-grey body, a short bony horn that develops on the forehead of adults and two forward-curving, knife-like blue spines on each side of the tail base. FishBase records a maximum fork length of 70 cm. Males have larger tail spines and slightly longer horns than females.
Taxonomy
- Family: Acanthuridae
- Genus: Naso
- Scientific name: Naso unicornis
- Described by: Forsskål, 1775
Habitat
The species is marine and reef-associated across the Indo-Pacific, from the Red Sea and East Africa to the Hawaiian, Marquesas and Tuamotu islands, north to southern Japan and south to Lord Howe and Rapa islands. Adults occupy channels, moats, lagoon and seaward reefs with strong surge, while juveniles use shallow protected bays and harbours; FishBase records depths of 0-180 m.
Tank requirements
- Minimum tank volume: 1500 L (396 gal)
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Specific gravity: 1.024-1.026
- Carbonate hardness: 8-12 dKH
- Strong water flow
- Lifespan: 10-25 years
Diet
Naso unicornis is herbivorous, feeding primarily on coarse brown algae, particularly Sargassum, as well as red algae with coarse or leafy blades. In aquaria it requires large quantities of marine algae and dried seaweed.
Compatibility
A semi-aggressive, diurnal mid-water swimmer, it is solitary or found in small schools and needs ample open swimming space. Wrasses, clownfish, angelfish and sturdy triggerfish make suitable tankmates, while other tangs of similar shape should be avoided in smaller systems. FishBase notes ciguatera poisoning has been reported from this species.
Reef compatibility
The species does not eat coral and is considered reef-safe, grazing brown macroalgae, although its large adult size demands a very spacious reef. Maintain carbonate hardness of 8-12 dKH and specific gravity of 1.024-1.026.
Conservation status
IUCN Red List: Least Concern, assessed in 2010 via FishBase.