Scopas Tang

Copyright www.jjphoto.dk

The species Zebrasoma scopas has several different English common names, such as Scopas tang, Brown scopas tang, Brown tang, Brushtail tang, Blue-lined tang, Bluelined sailfin tang, Brown sailfin tang, Brown sailing tang, Twotone tang, Two-tone surgeonfish, and Brown sailfin surgeonfish.

Zebrasoma scopas has not been evaluated for the IUCN Red List of Threatened Species.

Geographical range, habitat and habits

The Scopas tang lives in the Indo-Pacific from roughly 24°N to 34°S and from about 32°e to 78°w. Its geographical range stretches from East Africa (including the Mascarene Islands) to the Tuamoto Islands, and proceeds north up to southern Japan. Southwards, you can find this species down to Lord Howe and the Rapa islands.

The Scopas tang inhabits parts of lagoons and seaward reefs with prolific algae growth, from 1 to 60 meters / 3 – 200 feet. The Scopas tang spends most of its time grazing algae. Adults normally form small groups and will sometimes school, but you can also encounter specimens that live alone or in pairs. Groups and schools are not necessarily made up by Scopas tangs only; other tangs can also be included. Adult fish can roam over large parts of the reef, while juveniles tend to be more stationary. Juvenile Scopas tangs are solitary creatures that prefers to stay hidden among corals.

This species form resident spawning aggregations.

Size and appearance

The largest scientifically measured Scopas tang was 40.0 cm / 15.7 in.

This fish is dark brown ventrally and yellow dorsally. It is adorned with fine pale blue-green longitudinal lines that follows the scale rows and turns into dots anteriorly on both body and on head.

The body is almost disc-shaped and the snout is a bit extended. The mouth is filled with numerous small pharyngeal teeth. On each side of the caudal peduncle, there is a single white spine, the so called scalpel. This scalpel can inflict serious injury to other fish and is used for defence or to establish dominance. When it is not in use the fish will keep it folded down inside a groove.

Small juvenile specimens sport yellowish bars and more prominent yellow specks than adults. Juveniles are purplish and tend to have bigger dorsal and anal fins than the adults. The entire front half of the body is commonly comprised of thin vertical bars and spots, and the common name Twotone tang alludes to the colouration of the juvenile fish. The adult fish has an oval bristle-like patch (the setae) right in front of its peduncular spine which is not developed until the fish reaches a length of 7 cm / 2.8 in.

The exact colouration of a Scopas tangs varies from individual to individual. Some specimens look almost black, while others are more brownish or even yellow. Variants with different colour splotches across the body exist. Black specimens are sometimes erroneously sold as Zebrasoma rostratum (Black tang).

Scopas Tang care

The Scopas tang needs plenty of open water for swimming as well as suitable hiding spots and housing it an aquarium smaller than 75 gallons / 285 litres is not advisable. Keeping this fish in a too small aquarium can make it very skittish. Ideally include Acropolis coral skeletons in the set up.

Keeping Scopas tangs together in the aquarium is not advisable since they are aggressive towards each other. Members of the same genus should also ideally be avoided, especially if they are of similar size. Keeping specimens of dissimilar size and introducing the biggest ones last will decrease the risk of violence. Scopas tangs are equipped with sharp spines that can be used to slash other fish, but they are normally only used to attack members of its own genus. When not in use, the spines are kept tucked into sheath on the caudal peduncle.

The water temperature should be 72-78º F /22-25.5º C when housing Scopas tangs. The recommended pH-value is 8.1-8.4 and the specific gravity should ideally be kept at 1.020-1.025. Powerful water movements are very important. Do not allow the oxygen level to sink when keeping Scopas tang.

Well-fed scopas tangs are generally reef safe, but hungry specimens can start picking on sessile invertebrates, including large-polyped stony corals and soft corals. Just like many other members of the genus Zebrasoma, the Scopas tang is also fond of picking at the “mouth” of large-polyped stony corals to make them release excess zooxanthellae. This is generally not harmful for the coral.

The large and powerful Scopas tang may inadvertently topple corals in the aquarium and can therefore be a good idea to keep the corals glued down.

Be careful when handling a Scopas tang, because the “scalpel” can inflict painful wounds. If you are injured the affected area may swell up and change colour, and the pain can last for hours. There is also a high risk of infection.  

Feeding Scopas Tang

In the wild, the Scopas tang feeds chiefly on micro and macro algae. It will however ingest tiny animals that live among the algae as well, and it must therefore be given both herbivore and carnivore food in the aquarium to stay healthy in the long run. (The bulk of its diet should always be herbivore.)

Feed your fish many small portions throughout the day instead of just one or two large meals. This is not a finicky eater and it will readily investigate virtually any type of food. You can for instance use high-quality spirulina flakes rich in vitamin C as a base and supplement with dried macro-algae, fresh algae, and boiled vegetables. Also give the fish occasional servings of mysis shrimp, brine shrimp or similar meaty foods. Natural algae growth should be encouraged in the aquarium since this provides the fish with a constant food source and allows it to carry out its natural grazing behaviour. It is however unwise to relay on naturally algae only; always complement with other foods.

The Scopas tang stores fat inside its body cavities and can therefore survive periods of non-feeding. Juveniles do however have a really high metabolism and will rapidly waste away without food.

Breeding Scopas Tang

It is hard to sex Scopas tangs based on outer appearance. The male fish does however tend to be somewhat bigger than the female, and the bristle-like patch of setae located just in front of the peduncular spine is longer on males than on females. Some males change their colours when spawning.

This species form resident spawning aggregations in the wild and both group and pair spawning have been observed. Eggs and sperm is scattered into the water column.

We do not have any information about breeding Scopas tangs in aquariums.

Surgeonfish - Tang Articles:

Achilles Surgeonfish – Acanthurus achilles
Atlantic Blue Tang – Acanthurus coeruleus
Blue Hippo Tang – Paracanthurus hepatus
Chevron Tang – Ctenochaetus hawaiiensis
Clown Surgeonfish – Acanthurus lineatus
Convict Surgeonfish – Acanthurus triostegus
Desjardinii Tang – Zebrasoma desjardinii
Kole Tang – Ctenochaetus strigosus
Mimic Surgeonfish – Acanthurus pyroferus
Naso Tang – Naso lituratus
Orangeshoulder Surgeonfish – Acanthurus olivaceus
Powder Blue Tang – Acanthurus leucosternon
Powder Brown Tang – Acanthurus japonica
Purple Tang – Zebrasoma xanthurum
Sailfin Tang – Zebrasoma veliferum
Whitecheek Surgeonfish – Acanthurus nigricans
Yellow Tang – Zebrasoma flavescens