Humpback Unicornfish

The Humpback Unicornfish stands out for 2 obvious reasons. Its distinctive humped back and the horn that protrudes from the top of the males' head. While it may not have striking patterns or colours, it does have a unique appearance. The body is a greyish colour with paler bands running down its' sides. A succession of dark spots start at its' tail and spread out along the middle of its' body. Behind its' head are several paler spots. Like other Surgeonfish, it has caudal spines on either side of its' body where the tail starts. Unicornfish are among the hardiest Surgeonfish. Due to their size, they need an exceptionally large aquarium. Adults can reach a length of 90 cm (3 feet).

Very little is known about the breeding behaviour of Humpback Unicornfish. Males are larger than females and they spawn in pairs.

This species is native to the Indo Pacific. From the East coast of Africa to Indonesia, Philippines, Australia and Vanuatu. They usually stay in reef areas at depths of between 15 -20 metres. Although this can vary between 8 metres and 30 metres.

Tank Recommendations for Humpback Unicornfish

Make sure your tank is at least 360 gallons (1363 litres).

Water movement needs to be strong with good oxygenation. There should also be lighting which encourages algae growth in the tanks and on rocks.

Fish this size need plenty of space for swimming with lots of live rock and coral for shelter and grazing. They hide in caves and crevices overnight, so the gaps in the rock must be large enough for your specimen.

Suitable Tank Buddies

Unicornfish, have a reputation for being more mellow than other Surgeonfish. But they are still aggressive with their own kind and similar species. Apart from the potential hostility, tank size also needs to be considered. You will need an even bigger tank to accommodate more than one individual.

Usually Compatible

Most smaller fish are safe to co-habit with the Humpback Unicornfish. This includes peaceful fish such as Gobies and Fairy Wrasses. More aggressive fish such as Damselfish, Dottybacks and Clownfish should also be fine.

Sometime Compatible

The only suitable Tangs are ones of a different size, shape, colour and genus. More aggressive predatory fish such as Groupers and Lionfish are ok if they are smaller.

Rarely Compatible

Conspecifics are not suitable, also avoid aggressive Triggerfish. Pipefish and Seahorses are too delicate. Assessors will be too intimidated and stay in hiding. Frogfish may try to eat smaller Unicornfish.

Feeding your Humpback Unicornfish

Humpback Unicornfish are herbivores. In the wild, they feed on benthic algae. They can adapt to aquarium food and will eat various algae and plant-based diet which includes some meaty food. Marine algae, seaweed such as Nori, Spirulina, food flakes and pellets are suitable. They will also consume items like Brine Shrimp and Mysis Shrimp. Between feeding, they will graze on naturally on algae in the tank. You should feed them 3 times per day.