Blue Tang

Environment

Reef aquarium of at least 600-800 liters minimum for an adult (reaches 25-30 cm). Requires very large open swimming space. Stable marine water: temperature 24-27°C, pH 8.1-8.4, salinity 1022-1025 (33-35 g/L), KH 7-12°dKH, calcium 400-450 mg/L. Décor with live rock providing hiding places and algae for grazing. Lighting favoring algae growth. Moderate to strong water flow, excellent filtration and efficient protein skimmer. Very sensitive to nitrates (< 20 mg/L ideally). Mature aquarium essential (6 months minimum).

Feeding

Herbivore to omnivore with dominant plant-based diet. Dietary base: marine algae (nori, spirulina), blanched vegetables (spinach, zucchini), algae-based frozen preparations. Supplement with occasional meaty foods (brine shrimp, mysis). Feed 2-3 times daily in small amounts. Constant grazing of algae on live rock is essential for digestive and immune health.

Health & common diseases

The blue tang is particularly susceptible to marine white spot disease (Cryptocaryon irritans) and marine velvet (Amyloodinium), which manifest as white spots or a grayish film on the body and scratching behavior. It can also develop head and lateral line erosion (HLLE) due to nutritional deficiencies or poor water quality, recognizable by holes or lesions on the head. Strict quarantine of new arrivals, a varied diet rich in algae and vitamins, and optimal maintenance of water parameters help prevent most diseases. Caution: this species is very stressed by handling and copper treatments must be dosed carefully.

Tips & tankmates

Peaceful cohabitation, compatible with most non-aggressive reef fish. Can cohabit with other tangs if introduced simultaneously and in large volume. Beware of the caudal blade (scalpel) during handling. Very sensitive to stress, diseases (Cryptocaryon, Amyloodinium) and poor water quality. Slow acclimation essential. Quarantine introduction strongly recommended. DO NOT keep in small volumes: it is a tireless swimmer that suffers in confined space. Often sold as juveniles: anticipate the imposing adult size (25-30 cm). Avoid impulse buying linked to animated films.

Sources

• FishBase - Paracanthurus hepatus
• Reef2Reef - Blue Tang Care Guide
• LiveAquaria - Hepatus Tang
• Seriously Fish - Marine Species