Rock flower anemones are a reef-safe alternative to BTAs. Origin: Caribbean. Size: 3-6 inches expanded, 1-2 inches retracted. Sting: minimal - safe with corals, won't roam through tank. Colors: red, orange, blue, green, purple, "ultra" rainbow morphs. Premium ultra RFAs sell $80-300+. Lighting: medium PAR, 100-200, photosynthetic. Feeding: mysis or chopped silversides 1-2x weekly. Tankmates: reef-safe fish; clownfish occasionally host but not reliably. Care diff: beginner. Why preferred over BTAs: stays put (BTAs roam + sting corals when they move), peaceful with other corals, smaller footprint, easier to feed, gorgeous color variety. Reproduction: divides into clones in mature systems - one becomes a colony of 5-10 over 1-2 years.
Reviewed by the Fast Aquatics husbandry team · Updated May 2026
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