Achilles Tang (Acanthurus Achilles)

Care Level : Expert Only

Temperament : Semi-aggressive

Color : Purple, Tan

Diet : Herbivore

Reef Compatible : Yes

Water Conditions : sg 1.020-1.025, 72-78° F, dKH 8-12, pH 8.1-8.4

Max. Size : 10"

Origin : Pacific Ocean

Family : Acanthuridae

Minimum Tank Size : 180 gallons

Acanthurus Achilles, commonly known as Achilles Tang or Achilles Surgeonfish, is a tropical marine fish native to the Pacific Ocean.

The Achilles Tang is dark brown to purple in color. It has bright highlights of white and orange around the dorsal, caudal, and anal fins. A white marking is also present on the gill covers and a striking orange teardrop is found near the caudal fin. The juveniles of this species have an orange marking by the tail in the shape of a streak instead of being teardrop in shape. Acanthurus Achilles are black with striking orange and white lining along the fish's fins and tail. When the fish matures, a prominent orange drop shape develops on the caudal area, terminating into a sharp spine. They are a medium surgeonfish reaching a maximum of 25 cm (10 in) at adulthood.

A 180 gallon aquarium or larger is necessary to provide plenty of swimming room, and these fishes require strong water flow as they are normally found in surge zones. Aquascaping your tank’s interior to offer open swimming spaces with lots of hiding spots should suit an Achilles Tang better than a reef piled to the brim with live rock. A constant grazer, this fish is best kept in a well-established aquarium with a hardy growth of marine algae to graze on at its leisure. 

The Achilles Tang can be quite aggressive toward others of their species and toward other surgeonfish. It's, therefore, best to keep only one in a tank. They can, however, interact peacefully with other small, peaceful fish. 

The Achilles Tang is herbivorous, eating mostly benthic algae. They will also accept frozen and meaty foods such as brine shrimp and mysis shrimp in captivity. As with all surgeonfish, algae or similar vegetable matter should be included in their dietary intake to moderate aggression and regulate metabolic functions.

Size: Juvenile Small: 2" to 3"; Medium: 3" to 4"; Juvenile/Young Adult, Large: 3" to 4"; Adult Small: 3" to 3-1/2"; Small/Medium: 3-1/2" to 4"; Medium: 4" to 4-1/2"; Medium/Large: 4-1/2" to 5"; Large: 5" to 6"; X-Large: 6" to 7-1/2"