This star is a Culcita, if I recall the picture. VERY large, and quite predatory, IME. Though I was initially worried we wouldn't be able to feed it when it arrived at the LFS I worked at, I was less concerned when I saw it had pinned and was consuming a long spine urchin. I definitely would not put them in a reef, and based on the one I saw it would need probably at least a 130-150g to start just based on its space needs. I don't know how large the one's they have are.
Anyway, not commonly seen in the hobby, and I would argue that this is for a reason....