Achilles tang
Acanthurus achilles
Also known as Achilles Surgeonfish, Redtail Surgeonfish, Redspot Surgeonfish
SaltwaterFish
Care at a glance
- Temperature
- 75–81°F
- 24–27°C
- pH
- 8.1–8.4
- Adult size
- 9.4 in
- 24 cm
- Minimum tank
- 180 gal
- 680 L
- Temperament
- Aggressive
- Social behavior
- Solitary
- Own kind
- One per tank
- Tankmates
- With caution
- Swim level
- Middle
- Diet
- Herbivore
- Difficulty
- Difficult
- Breeding
- No record
- Rarity
- Rare
- Reef safe
- Reef safe
- Family
- Acanthuridae
- Origin
- Western and central Pacific reefs, from Oceania to Hawaii and Pitcairn Island
Overview
The Achilles tang is a surgeonfish for a large, mature reef tank. It is one of the toughest tangs to keep long term, so it is a fish for experienced keepers only.
Did you know
The Achilles tang is named for the bright orange-red teardrop near its tail. That mark sits just in front of the sharp scalpel spine that gives surgeonfish their name.
Caring for the Achilles tang
Give an Achilles tang at least 180 gal (680 L) in a mature, stable reef tank. It evolved in the surge zone for strong, turbulent flow and high dissolved oxygen, which are hard to match in a closed aquarium. Aim extra powerheads at it, since recreating that turbulence is one of the few things that seems to keep it content.
Hold the water at 75 to 81°F (24 to 27°C) with a pH of 8.1 to 8.4, and keep it steady. This tang reacts badly to any dip in water quality and is a well-known ich magnet. Give it a long quarantine before it ever reaches the display.
Build its diet around marine algae and nori. The Achilles tang is reef safe, so it can share a tank with corals.
Keep only one per tank. It ranks among the more aggressive surgeonfish, toward its own kind and toward other tangs in general. Make it the only Acanthurus or Naso species in the tank, and pick its other tank mates with caution.
Good to know
Acanthurus achilles belongs to the surgeonfish family, Acanthuridae. Apart from its tail marking, the body is a deep blue-black, with electric blue edging along the fins.
In the wild
Achilles tangs live in the surge zones of Pacific reefs, from Oceania and the Hawaiian Islands out to Pitcairn Island. These are the shallow, wave-battered edges where oxygen-rich water crashes over the reef crest. They usually live alone or in small loose groups, picking algae off the rock in the wash.
Common questions
What size tank does an Achilles tang need?
An Achilles tang needs at least 180 gal (680 L). It spends most of its time in the middle.
What temperature and pH does an Achilles tang need?
An Achilles tang is comfortable at 75–81°F (24–27°C) with a pH of 8.1–8.4.
How big does an Achilles tang get?
An adult Achilles tang reaches about 9.4 in (24 cm).
Related species
9.1 in (23 cm)124 gal (470 L)75–81°F (24–27°C)Powder blue tang
Acanthurus leucosternon
9.1 in (23 cm) · 124 gal (470 L)
15 in (38 cm)238 gal (900 L)75–81°F (24–27°C)Clown tang
Acanthurus lineatus
15 in (38 cm) · 238 gal (900 L)
15.7 in (40 cm)180 gal (680 L)75–82°F (24–28°C)Sohal tang
Acanthurus sohal
15.7 in (40 cm) · 180 gal (680 L)
10.6 in (27 cm)124 gal (470 L)75–82°F (24–28°C)Convict tang
Acanthurus triostegus
10.6 in (27 cm) · 124 gal (470 L)
8.3 in (21 cm)129 gal (490 L)75–81°F (24–27°C)Powder brown tang
Acanthurus japonicus
8.3 in (21 cm) · 129 gal (490 L)
11.4 in (29 cm)129 gal (490 L)75–82°F (24–28°C)Mimic tang
Acanthurus pyroferus
11.4 in (29 cm) · 129 gal (490 L)