Indo-Pacific, mainly Indonesia and the western Pacific
Water
saltwater
Care level
intermediate
Reef safe
yes
Lighting
Moderate
Flow
Moderate
Care
Yellow polyps are a zoanthid with slender, bright yellow polyps carrying long, thin tentacles, joined at the base. They often form dense clusters over rock and look like small yellow flowers. Place them low to mid in the tank in moderate light and moderate flow. They are photosynthetic but get much of their food from feeding, so they suit a reef where you target feed. Water: keep a standard reef: about 24–26 °C, pH 8.1–8.4, alkalinity around dKH 8–11. Naming: the hobby name Parazoanthus gracilis is uncertain, and studies suggest the yellow polyps in the trade may belong to a different genus. Safety: zoanthids and palythoa can contain palytoxin, a dangerous toxin. Wear gloves and eye protection when handling or fragging them, and never boil, scrub or pressure-wash rock that carries them. Neither LiveAquaria nor Top Shelf Aquatics lists this species; the figures are general guidance for the genus, not from a source. Not CITES-listed. Sources: general reef-keeping guidance; neither LiveAquaria nor Top Shelf Aquatics lists this species. Checked October 2026.
Diet
Partly photosynthetic. Feed fine meaty foods such as mysis, brine shrimp or zooplankton several times a week for the best growth.
Breeding
Easy. Cut a patch of polyps from the rock with a scalpel and glue it to a plug with cyanoacrylate gel. Wear gloves and eye protection.
Compatibility and tank mates
Mildly aggressive: they can sting neighbours and spread over nearby rock. Give them 5–10 cm of space.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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