This is probably a species of Echinaster. It is probably reef safe, but no guarantees. We don't know a lot about the wild diet of these animals. I know a few people keep them, and I believe they have them in reefs.
A long acclimation is required for these stars, just like Linckia. We are talking about 4+ hours (the longer the better) using a drip method.
I do not recommend that they go in a tank with any other similar star (eg a Linckia or Fromia) unless it is a large system (100g+). They usually can not be spot fed (though some may have had success) and rely on lots and lots of LR and a healthy mature system. They will eat algal and bacterial films, bryozoans, sponges and other encrusting animals on the LR....and potentially other things as well. IMO, a 55g with at least 55lbs LR is minimum for best success. Many seastars of this group (the reef safe stars) do not survive past the 1 year mark, and likely die of starvation.
