Acanthurus leucosternon — Powder Blue Tang
Family: Acanthuridae
Origin: Indian Ocean — from the Maldives and Sri Lanka to the east coast of Africa and Indonesia
Size: Up to 23 cm (9 inches)
Lifespan: 10–15 years in captivity with proper care
 
Natural Habitat
Environment: Coral-rich lagoons and seaward reefs with plenty of rockwork
Water Conditions: Warm, well-oxygenated tropical saltwater
Temperature Range: 24–28°C (75–82°F)
 
Physical Description
Body Shape: Oval and laterally compressed
Coloration:
Bright powder-blue body
Jet-black face mask
White chest and yellow dorsal fin
Fins: Sharp caudal peduncle spines (used for defense); yellow dorsal fin is a key visual feature
 
Aquarium Care
Tank Size: Minimum 125 gallons (475 litres); larger preferred due to high activity level
Water Parameters:
pH: 8.1–8.4
Salinity: 1.020–1.025 SG
Temperature: 24–28°C (75–82°F)
Water Flow: Moderate to strong
Substrate: Sand or crushed coral
Décor: Live rock with grazing surfaces and open swimming space
Filtration: High-capacity reef filtration with excellent oxygenation and stability
 
Diet
Type: Primarily herbivorous
Preferred Foods:
Marine algae, seaweed (nori), spirulina
Supplement with mysis shrimp and enriched pellets
Feeding Frequency: 2–3 times daily in small portions
 
Behavior & Tank Mates
Temperament:
Territorial toward other tangs and surgeonfish
Active swimmer; benefits from stable tank dynamics
Compatible Tank Mates:
Peaceful reef-safe species (clownfish, gobies, blennies, wrasses)
Avoid aggressive tangs or other Acanthurus species in small tanks
Behavior Notes:
Highly sensitive to stress and water quality changes
Prone to marine ich; requires a mature, stable aquarium
 
Breeding
Spawning Method: Broadcast spawner
Breeding Conditions:
Not bred in home aquariums; requires large, specialized systems
Fry Care:
Planktonic larvae; commercial breeding success is extremely limited