Well you do have those orange spot polyps. If i were going to buy a star, i would buy a
Fromia monilis (orange star) or a chocolate chip star, since i know these would go into smaller tanks. Reef stars are very weak, since they lack the regeneration abilities of other stars. You need near perfect water conditions to keep them alive, as well as an extensive supply of things to eat.
Starfishes do not eat in a conventional method, they invert their stomachs into a molluscs shell and digest the contents. So if you buy a star, you cant have bivalves. Also, you must give them mussel meat or a similiar meaty food. Have a good supply of this.
I am planning to purchase one after we move, it has to be
after we move 1) because my tank is not yet mature, 2), if you take them out of the water they will nearly always die, and 3) any change in the water chemistry of any kind is not tolerated by the starfish. If they die, they may drag other animals down with it, since they release toxins into the water.
If you are willing to commit to one, then be my guest. The are wonderful animals if taken care of properly.
-Lynden