Paracanthurus hepatus — Blue Tang (also known as Regal Tang, Palette Surgeonfish)
Family: Acanthuridae
Origin: Indo-Pacific region — from East Africa to Japan, Micronesia, and the Great Barrier Reef
Size: 25–30 cm (10–12 inches)
Lifespan: 8–20 years in captivity
 
Natural Habitat
Environment: Coral reefs and reef slopes with abundant cover and algae growth
Water Conditions: Warm, stable, tropical saltwater with high water quality
Temperature Range: 24–28°C (75–82°F)
 
Physical Description
Body Shape: Deep-bodied, laterally compressed with small mouth
Coloration: Bright royal blue body with a black "palette" marking and vibrant yellow tail
Fins: Continuous dorsal fin, sharp scalpel-like spines at the base of the tail (used defensively)
 
Aquarium Care
Tank Size: Minimum 100 gallons (380 litres) for juveniles; 180+ gallons recommended for adults
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 for grazing and hiding; open swimming space required
Filtration: Strong reef-capable filtration with protein skimming and stable parameters
 
Diet
Type: Omnivorous (primarily herbivorous grazer)
Preferred Foods:
Marine-based algae (nori, spirulina), mysis shrimp, high-quality marine pellets
Regular vegetable matter to support gut health
Feeding Frequency: 2–3 times daily in small portions
 
Behavior & Tank Mates
Temperament:
Generally peaceful but can be territorial with other tangs
Active swimmer that needs room to roam
Compatible Tank Mates:
Most peaceful reef fish (clownfish, gobies, wrasses)
Avoid other Acanthurids unless tank is very large
Behavior Notes:
May become shy or stressed in tanks that are too small or crowded
Prone to marine ich if water quality fluctuates
 
Breeding
Spawning Method: Broadcast spawner
Breeding Conditions:
Not bred in typical home aquariums
Commercial breeding is rare and requires large-scale marine systems
Fry Care:
Larvae require planktonic foods and highly specialized conditions