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Bluespine Tang


Bluespine Tang, Naso Unicornis

The Bluespine Tang is also known as the Unicorn Tang, the Bluespine Unicornfish, the Unicorn Tang, the Green Naso Tang and the Large or Bignose Unicornfish. It is found in shallow tropical reef waters of the Indo-Pacific from the Red Sea to Hawaii. They like crevices and outcroppings in the outer reef area and can be found to depths of more than 30 m. Juveniles are green and turn more gray and blue with age. There is a blue edge on the dorsal and anal fins, giving rise to the name "bluespine". The spines at the base of their tail, typical of all tangs, are colored bright blue in the Bluespine Tang. The spines are easily tangled in nets. The distinctive unicorn feature does not develop until after they are approximately 6 inches in size. The tail becomes squared in adults and develops long streamers at the tips.

An aquarium of at least 200 gallons is recommended. It should have hiding places, plenty of live rock and large open areas for swimming. The water should be very clean and clear. In the wild, the Bluespine Tang mainly eats algae, especially Sargassum seaweed. Bluespines should be introduced into a tank with an abundance of algae. Other suitable foods include lettuce, broccoli, spirulina, veggie clips, nori, brine shrimp and mysis shrimp. Feeding should be done several times per day nori (natural dried seaweed). Bluespine Tangs can be trained to take food directly by hand.

Bluespine Tangs are compatible with most saltwater fish but should not be combined with other tangs or triggerfish. Wrasses may be a good choice to share their tank. Bluespine Tangs are also aggressive toward their own species, so one Bluespine is probably a good maximum for your tank.

There are no distinguishable differences between males and females, though some readers indicate the males have a more pronounced "unicorn". Bluespine Tangs are not successfully bred in captivity.

Bluespine Tang, Naso Unicornis

Bluespine Tang, Naso Unicornis

Bluespine Tang, Naso Unicornis

Bluespine Tang, Naso Unicornis
Bluespine and Orange Spot Tangs

Scientific Name: Naso unicornis
Family: Acanthuridae
Care: Normal
Temperature: 22 - 26 C; 72 - 79 F
pH: 8.1 - 8.4
dH: 8 - 12
Specific Gravity: 1.020 - 1.025
Size: 60 cm; 24 inches
Breeding: Egg Layer
Life Span: 20 years
Crustacean Safe: Yes
Coral Safe: Yes


Only one Bluespine per tank is recommend.  They may act aggressively towards other species of tangs, so they are best kept as the only tang species in the tank as well.  Suitable tank mates include Blennies, Angelfish, Damsels and Wrasses.