Orange Shoulder Tang (Acanthurus Olivaceus): Ultimate Care Guide

Native to Indo-Pacific waters, the Orange Shoulder Tang sports a bordered orange line above their pectoral fins when mature. Juveniles are bright yellow, without a hint of the orange “shoulder” markings or gray body color seen on adults. Young Orange Shoulder Tangs look so different from their adult versions that it is easy to mistake juvenile fish for another species entirely!

An active swimmer, the Orange Shoulder Tang will need a large aquarium. This fish can grow up to 14 inches long and will do best in tanks surpassing 135 gallons. Because of their adult size, Orange Shoulder Tangs are more often seen in commercial aquarium installations.

This species is mostly reef safe as long as it has a steady supply of quality nutrition. If it goes hungry, it may start attacking corals. It can be a good idea to install a refugium to cultivate edible algae for this species. Orange Shoulder Tangs are large and energetic swimmers that will eat a lot. Plan for enough food supply, especially as your fish matures.

If you have a large enough tank, this fish can be a great addition. Let’s go over some of what you’ll need to know to care for this active fish!

Orange Shoulder Tang Care

Orange Shoulder Tang need large tanks and can be susceptible to developing Ich when they are not well taken care of. Due to their specific care requirements, this species is best kept by moderately experienced hobbyists.

Temperature

Orange Shoulder Tang need water temperature between 75° – 82° F (24° – 28° C).

Water pH

Water pH for Orange Shoulder Tang should be between 8.1 and 8.4. This is a sensitive species, so take care to keep pH and other water parameters steady.

Orange Shoulder Tang (Acanthurus Olivaceus)
Orange Shoulder Tang (Acanthurus Olivaceus)

Orange Shoulder Tang Size

Orange Shoulder Tang can grow up to 14 inches long. This large final size can be a surprise. Make sure your tank has enough volume to support this fish as an adult.

Food & Diet

Orange Shoulder Tangs are omnivores but mainly consume algae and plant matter. This is an active fish so you’ll likely need to supplement their diet with marine sourced dried algae.

They will feed on all types of algae, including brown algae and will pick through sand and live rock. Be cautious as they can quickly exhaust this food source. If you maintain a refugium with edible macroalgae this can provide a great addition to your Orange Shoulder Tang’s diet.

Orange Shoulder Tang Lifespan

In the wild, Orange Shoulder Tangs can live up to 35 years. In an aquarium, a lifespan of 5 to 10 years is more common.

Orange Shoulder Tang Tank Size

Orange Shoulder Tangs can grow to 14 inches and are active swimmers. Plan for at least a 135 gallon aquarium. 180 gallon or above is best. This fish is more commonly seen in larger commercial aquariums due to its greater space needs. A hobbyist who plans to keep an Orange Shoulder Tang needs to be aware of how much space a fully mature specimen requires. Without enough swimming room this fish can have issues with aggression and can succumb to stress related illness.

A long tank would be a good pick as this species likes to have lots of horizontal swimming space. You will also likely install one or more powerheads to give your Orange Shoulder Tangs current to swim against. This setup might annoy other tank members who aren’t comfortable with strong currents so you’ll want a tank large enough for other fish to escape strong powerhead flow.

Tank Setup

An Orange Shoulder Tang will need a large tank, live rock, live sand, and a power head outlet to produce strong currents. Plan to have powerheads in at least one part of your tank. Your Orange Shoulder Tang will appreciate having an area where they can swim against the current. Be careful not to overdo this as many other tank inhabitants may not appreciate the strong flow.

Provide enough caves and areas for hiding spaces. This species will graze live sand and live rock in its endless search for algae. It is likely you won’t have enough rock or sand in you tank to provide all the food this fish needs. Consider including a refugium to grow edible algae to supplement their diet.

A refugium can be a good idea for a larger tank as many other tank mates will appreciate the steady supply of copepods and other microfauna. A large tank will probably be home to many species apart from an Orange Shoulder Tang. Take these into account when installing your refugium. A common refugium size is 20% of the volume of the attached display tank. If you need to cultivate large amounts of copepods and algae you might need more than this. It is often recommended to get the largest refugium you can afford for your tank setup. This is especially true if you are planning to feed your Orange Shoulder Tang with cultivated algae.

When stocking your tank it is best to add the Orange Shoulder Tang first, if possible. This species will like some time becoming accustomed to a tank before having to deal with tank mates. This can also be a dangerous time, as new tanks can be subject to water quality swings. Check your water quality and adjust as needed.

Orange Shoulder Tang Breeding

Orange Shoulder Tang have not yet been bred in captivity. Currently all specimens in captivity are live caught.

Orange Shoulder Tang, like other surgeonfish, are broadcast spawners. After their courtship ritual, the female will release her eggs close to the surface. The male follows and fertilizes the eggs. The eggs drift with the ocean current. Once hatched, the fry will feed on plankton before moving to calmer water to mature.

Orange Shoulder Tang Juveniles

Orange Shoulder Tang juveniles are solid yellow. They look so different from their mature versions that they can be mistaken for another species.

Growth Rate

Orange Shoulder Tangs will grow to full maturity in around 4 to 5 years. This species can go from a 3 inch juvenile to a fully grown 14 inch adult in this time.

Orange Shoulder Tang Male or Female

It is difficult to sex Orange Shoulder Tang. The females can be slightly larger than males. Unlike some species, they do not switch genders. Sex identification is less important with this species as both sexes look similar. They have not been bred in captivity.

Disease

Orange Shoulder Tangs are particularly susceptible to Ich. When adding this species to a display aquarium you will want to watch them in a quarantine tank (QT) for a few weeks. It is always a good idea to have a QT available in case this fish becomes infected. Ich and other diseases are treatable but the medications used can harm corals or other reef inhabitants. Any treatment should be applied only to an infected fish, and not broadcast in your display tank.

Orange Shoulder Tang Tank Mates

Orange Shoulder Tangs are generally peaceful tank members. They can have difficulty with members of their own species unless they are added to the tank at the same time. They can live with other surgeonfish but the Orange Shoulder Tang should be added first.

When trying to keep multiple Orange Shoulder Tangs, ensure enough tank volume. One fully grown specimen will happily range over a 200 gallon aquarium. Multiple Orange Shoulder Tangs should be attempted with caution if at all.

Are Orange Shoulder Tang Aggressive?

Orange Shoulder Tangs are known to be fairly peaceful when provided with enough tank space and enough food. They can attack corals and sometimes other fish when hungry or cramped. Keep your Orange Shoulder Tang peaceful with a large aquarium and a steady diet of quality food.

Examples of Compatible and Incompatible Tank Mates

Orange Shoulder Tangs aren’t as aggressive as other Tangs and will get along with a broad range of common reef tank inhabitants. This makes for easy setup of community tanks. Gobies, Blennies, Clownfish, Damselfish, Mandarins and Dwarf Angelfish will all coexist with your Orange Shoulder Tang.

For best results you’ll want to add an Orange Shoulder Tang to a new tank first. They like exploring territory and picking hiding spots without having to consider other fish.

It may be possible to add a second Orange Shoulder Tang to a tank as long as the new addition is a juvenile. Note that they can still have problems as the younger fish matures. They may eventually compete for territory.

Where can I find Orange Shoulder Tang for sale?

Orange Shoulder Tang are available from your local fish store and Internet sources. All specimens are wild caught so expect higher prices. You may have to be added to a waiting list.

Orange Shoulder Tang Price

Orange Shoulder Tang are priced according to size. Small specimens less than 3 or 4 inches are usually less than 80 USD. Larger ones of 5 or more inches can be over 250 USD.