Platygyra

Platygyra is a genus of massive, dome-shaped brain coral with long valleys that meander like a maze. The walls separating the valleys are thick and their septa look jagged. The walls are usually brown and the valley floors gray or green; fluorescent green forms are common in the trade. Identification to species level is difficult in the store, so this page covers the genus as a whole. Its trade is subject to CITES Appendix II; choose a maricultured colony or an aquacultured frag.

• Light: Moderate, about 100–250 PAR; in the wild it lives in shallow, brightly lit waters.
• Flow: Moderate and variable; detritus should not collect in the valleys.
• Placement: The middle zone of the rockwork.
• Water parameters: Salinity 1.024–1.026, KH 7–10 dKH, calcium 400–450 mg/L, magnesium 1250–1350 mg/L; stable values are important.

It is photosynthetic and gets most of its nutrition from light. Fine-grained coral food can be given once a week to the short tentacles that emerge from the valleys at night.

It opens short tentacles at night and can digest a coral it touches with its mesenterial filaments; leave at least 10 cm between it and its neighbors. It can be harmed if it meets aggressive LPS. Dwarf angelfish and butterflyfish may pick at the tissue.