Tangs · Acanthuridae
Care levelExpert
Bluespine Unicorn Tang
Naso unicornis
A short forehead horn, greenish-gray body and blue tail-spine plates distinguish adult Bluespine Unicornfish. It becomes a very large macroalgae browser, making it a specialist choice for exceptionally spacious adult housing.
Natural-history records reach about 70 cm fork length. Fish Match uses a conservative 500-gallon planning figure rather than treating smaller juvenile trade guidance as a complete adult housing plan.
Recommendation
Would you recommend this fish for a suitable saltwater aquarium?
500+ galRecommended tank
28 inchesAdult size
Semi-aggressive / territorialTemperament
Generally compatibleCoral safety
+ Why you’ll love them
- A short forehead horn, greenish-gray body and blue tail-spine plates distinguish adult Bluespine Unicornfish.
- Grazes marine algae as part of a balanced feeding plan.
- Generally compatible with corals when appropriately housed.
! Things to consider
- Needs adult-sized housing: plan for 500 US gallons or more with suitable swimming space.
- Natural-history records reach about 70 cm fork length. Fish Match uses a conservative 500-gallon planning figure rather than treating smaller juvenile trade guidance as a complete adult housing plan.
- Requires a consistent feeding routine and stable water.
- Has sharp tail spines; handle carefully.
Tank and habitat
- Recommended volume
- 500 US gallons or larger; allow for stocking and layout.
- Full-grown size
- 28 inches (maximum adult size)
- Tank footprint and swimming space
- Use a long, broad aquarium with substantial open swimming lanes and turning room. The listed volume is a starting point; an adult or crowded community may need a larger system.
- Tank maturity
-
6 months recommended
Use an established, fully cycled aquarium with stable filtration and productive grazing surfaces. Confirm water stability and reliable feeding access before introduction. Suggested tank age is a planning guide, not proof of readiness. Complete cycling, stable water and the right food supply are essential. - Habitat and equipment
- Provide good circulation and gas exchange. Arrange secure rockwork for shelter and grazing, keep open water available, and use a secure lid. Take care around the sharp tail spines.
Care and compatibility
- Temperament
- Semi-aggressive / territorial
- Why this care level
- Natural-history records reach about 70 cm fork length. Fish Match uses a conservative 500-gallon planning figure rather than treating smaller juvenile trade guidance as a complete adult housing plan.
- Suitable tank mates and conflicts
- Many appropriately sized marine community fish may be suitable. Other tangs, especially similar-shaped species, require particular care and substantially more space.
- Alone, pair or group
- A single tang is the simpler plan. Keeping several requires additional space, individual assessment and a way to separate incompatible fish; wild groups do not establish an aquarium stocking rule.
Corals and invertebrates
- Coral safety
-
Generally compatible
Generally compatible with corals, but observe the individual. Algae grazing should not be mistaken for a guarantee that no picking will occur. - Shrimp safety
-
Generally compatible
Generally compatible with ornamental shrimp; monitor introductions and individual behavior. - Snail safety
-
Generally compatible
Generally compatible with snails. Continue observing grazing behavior around small invertebrates. - Clam safety
-
Generally compatible
Usually compatible, but individual picking is possible. Monitor clam mantles and other sessile invertebrates, especially if feeding is inadequate.
Food and feeding
- Diet
- Herbivore; marine algae and varied prepared foods
- Feeding plan
- Provide substantial marine macroalgae and suitable herbivore preparations; confirm feeding and access before adding it. Offer food consistently and check body condition; natural grazing is a supplement, not a complete feeding plan.
- Prepared or live food
- Marine algae sheets, suitable herbivore pellets and varied marine frozen preparations can be offered. Confirm the individual accepts the foods you can provide.
Water conditions
- Temperature
- 72–78 °F (22–26 °C) is a commonly published aquarium reference range. Maintain stable conditions and consider the needs of the whole community.
- Specific gravity
- Specific gravity 1.020–1.025 appears in common species-care guidance. Match the needs of corals and other inhabitants, and avoid abrupt changes.
- pH
- pH 8.1–8.4 is the published marine aquarium reference range used here; maintain stability rather than chasing a single reading.
Long-term care
- Lifespan
- The linked references do not establish a reliable typical captive lifespan for this profile. Plan for long-term care and maintain a realistic adult housing commitment.
- Growth and future planning
- Natural-history references record up to about 70 cm fork length, approximately 28 inches. This is a reported maximum, not a typical aquarium growth target. Adult housing should account for its sustained swimming.
Before you buy
- Is this fish right for your tank?
- Have an exceptionally large, long-term home ready. An ordinary home reef is unlikely to provide a suitable adult swimming footprint.
- Buying checklist
- Ask to see the fish eat. Look for a well-filled body, clear eyes, intact fins and normal swimming and breathing. Plan quarantine and confirm the seller’s species identification and feeding routine.
User comments (0)