Hammer coral
Euphyllia ancora
Euphyllia ancora forms massive or dome-shaped colonies, with fleshy polyps ending in hammer- or anchor-shaped tentacles (sometimes T-shaped or anchor-like). Color ranges from green to brown, often with fluorescent tips (green, blue, purple). Polyps can reach up to 5 cm in length. The colony can grow to 30 cm in diameter. It possesses stinging sweeper tentacles that extend at night to defend its space. No visible sexual dimorphism.
Recommended parameters
| Parameter | Recommended range |
|---|---|
| Temperature | 24–28 |
| pH | 8.1–8.4 |
| KH | 8–12 |
| Salinity | 1.023–1.025 |
| NO₃ | ≤ 10 |
| PO₄ | ≤ 0.1 |
Care
Care notes
A minimum 100-liter tank is recommended for a small frag, but an adult colony needs 200 liters or more. Temperature 24-28°C, pH 8.1-8.4, salinity 1.023-1.025. Moderate lighting (PAR 100-200) and moderate flow. It is sensitive to parameter swings, especially stable alkalinity (8-12 dKH). It can be fed small prey (brine shrimp, mysis) once or twice a week. Beware of stinging sweeper tentacles: leave at least 15 cm of space from other corals. Avoid fish that nip at polyps (butterflyfish, angelfish).