Blue tang
Paracanthurus hepatus
Will it fit your tank?
Compare it with your tank's species, size, water tests and country.
Water
- Comfortable
- Acceptable, less ideal
- Tolerated, not comfortable
Space
Needs 300–681 L, depending on how it is kept
- The space it needs, from the least to the most generous
- Recommended
Character and care
- TemperamentPeaceful
- Social lifeIn groups
- DietHerbivore
- Reef safeYes
Legal rules
The least the law allows, by country: the water and space above are what the species needs. A tank is checked against its own country's rules.
Austria
9 rules
- A tank of at least 5000 L
- Temperature: 22–28 °C
- Salinity: 29.5–35 ppt
- pH 7.9–8.5
- Carbonate hardness: at least 7 dKH
- Ammonia: none
- Nitrite: none
- Nitrate: up to 50 mg/L NO₃
- Phosphate: up to 0.5 mg/L PO₄
2 notes from the rules
1–3 animals; 20 % more volume for each further animal
Austria, general duties for marine fish: aim for middle values; keep salinity within ±0.5 ppt of its mean and top up evaporation at short intervals; avoid heavy metals and treat with copper only in a separate tank; simulate tides, waves and currents; give a day–night cycle; use at least 200 L (100 × 50 × 40 cm) with filter, heater, cooling, pumps, protein skimmer, rockwork with hiding places, free swimming space and lime-rich, heavy-metal-free substrate; check equipment and temperature daily and other parameters every 14 days, and nitrite daily during the first six weeks; species kept together must suit each other in water quality, temperature and social behaviour (§ 7 (5); Anlage 5, 2.1).
Switzerland
4 rules
- At least 43.8 L of water per animal
- Tank length at least 75 cm
- Tank width at least 50 cm
- Tank height at least 25 cm
Note from the rules
Switzerland, general duties for ornamental fish: minimum volume = each fish's current body length (snout to tail base) × litres per cm by size class (up to 5 cm 0.5; 10 cm 0.75; 15 cm 1; 20 cm 1.25; 30 cm 1.75; 40 cm 2.25; over 40 cm 3), summed over all fish, plus species-specific needs; the tank at least 3 times as long and 2 times as wide as the largest fish's body length, and the water at least that deep; not visible from all sides, with visual cover and retreats; a day–night rhythm; water quality suited to the species; no prolonged strong vibration; social species need contact with their own kind; prevent excessive breeding; genetically modified fish such as GloFish are banned (TSchV Art. 13, 25, 98 and Anhang 2 Tabelle 8).