Cycloseris

Cycloseris are the small relatives of Fungia: round or slightly oval discs, usually 2–10 cm across, that live free on the sand. On the surface, fine, straight septa run from the mouth in the center to the edges. In the wild most are cream or greenish, but fluorescent and multicolored "rainbow" forms are sought after in the trade. Telling the species apart is difficult in the store, so this page covers the genus as a whole. Its trade is subject to CITES Appendix II; because the disc is also propagated in the aquarium by cutting it into wedges, captive-produced individuals can be found, so choose those.

• Light: Moderate, about 75–150 PAR; fluorescent colors become pronounced under blue-dominated light.
• Flow: Low and indirect; strong flow rolls the small disc over.
• Placement: On top of the sand; fine sand is preferred.
• Water parameters: Salinity 1.024–1.026, KH 7–10 dKH, calcium 400–450 mg/L, magnesium 1250–1350 mg/L.

It is photosynthetic. If fine-grained coral food or chopped mysis is placed on top of the mouth once a week, color and fullness improve.

It is peaceful; its short tentacles only have an effect on direct contact. Even so, leave 5–10 cm between it and other corals on the sand, because it can slowly move around. Keep it away from aggressive corals on the sand such as the elegance, open brain and Heliofungia. Sand-sifting gobies can bury the disc; hermit crabs can knock it over.