Zoanthus pulchellus

Zoanthus pulchellus is a zoanthid common on Caribbean reefs whose polyps are embedded in a shared tissue layer (coenenchyme). Because of this structure the colony looks less like individual polyps and more like a continuous carpet stuck to the rock. Polyp diameters range from about 0.3 to 1.3 cm; the oral discs are in shades of green, blue-green or brown. In the trade it is often sold without a species name as "mat zoanthid" or green zoanthid.

Palytoxin warning: Use gloves and protective eyewear; do not put rock with colonies in boiling water and do not scrub it out of the water.

• Moderate to strong light (about 100–250 PAR) and moderate flow.
• The middle zone of the rockwork; since it spreads with its shared tissue, a separate rock is ideal.
• Salinity 1.024–1.026, KH 7–11 dKH; keep phosphate and nitrate low to prevent hair algae.

It is photosynthetic and gets most of its nutrition from light. Fine powdered food or zooplankton can be offered occasionally.

It is not aggressive, but as it advances like a carpet it can cover the bases of neighboring corals. Leave 5–10 cm of clear space and trim the spreading edges. Zoanthid-eating nudibranchs and sea spiders are the biggest danger.