Black Tang

Species Profile

• Scientific Name: Acanthurus nigricauda
• Common Name: Black Tang (also known as Epaulette Surgeonfish)
• Adult Size: 12–14 inches (30–35 cm)
• Life Expectancy: 8–12 years in captivity (longer in the wild)
• Habitat:
  • Native to the Indo-Pacific region, from the Red Sea to Samoa
  • Found in lagoon reefs, coastal reefs, and outer reef slopes

  • Typically resides in turbid waters with sandy or rubble substrates

Tank Requirements

• Minimum Tank Size: 150 gallons (570 liters)
  Requires lots of swimming space and hiding spots
• Ideal Temperature: 75–82°F (24–28°C)
• pH Range: 8.1–8.4
• Water Hardness: 8–12 dKH
• Temperament:
  • Generally peaceful, but may become territorial with other tangs or similar-shaped species
  • Better kept alone or with tangs of a different genus

  • Active swimmer, best for larger reef or FOWLR tanks

Diet & Nutrition

• Primarily herbivorous
• Feeds on filamentous algae, detritus, and organic matter in the wild
• In captivity, offer:
  • Nori (seaweed)
  • Spirulina flakes/pellets
  • Algae-based frozen foods
  • Occasional mysis or brine shrimp as supplements

• Frequent grazing is important to mimic natural behavior

Breeding & Spawning

• Very rare in captivity
• In the wild:
  • Broadcast spawners—release eggs and sperm into the water
  • No parental care

  • Eggs hatch into planktonic larvae

Appearance

• Dark brown to black body
• Horizontal pale streak across the midsection
• Long, sleek body typical of surgeonfish
• Eyes may have a white or pale ring

• Crescent-shaped tail fin

Distinctive Features

• Named for the distinctive black coloration
• Possesses a scalpel-like spine on either side of the tail used for defense

• Can be confused with Acanthurus gahhm (Black Surgeonfish) but nigricauda has a paler horizontal stripe