Anchor Coral

About

Anchor coral (Euphyllia grandiseptata) is a large-polyp stony coral that grows in a phaceloid form, meaning its skeleton develops as a cluster of irregular, finger-like branches rather than a single fused mass. Each branch is relatively slender, typically somewhere in the range of 15 to 25 mm across, with a skeletal structure built around thick, prominent primary septa that dwarf the smaller ones between them. The walls themselves are thin, and the external ribbing is widely spaced and delicate. In the aquarium, none of that skeleton is visible during the day. What you see instead are the extended tentacles, which carry a distinctive blue-grey coloration that sets this species apart from the more commonly kept hammer and frogspawn corals it resembles. Those tentacles sway with gentle water movement, which is exactly the kind of moderate, indirect flow this coral appreciates. It shares the Euphyllia genus with several close relatives, and the resemblance can make identification tricky even for experienced reefers. Care falls into the intermediate category. Not a coral for someone just starting out with a reef tank, but very manageable once you have a stable system and a feel for LPS husbandry. Keep neighbors at a safe distance, as Euphyllia corals are capable of extending sweeper tentacles to sting nearby competitors.