Agreed Sand sifting stars need to be feed if your tank is not 75g or bigger. I didnt want to say this, Well for a couple reasons, I have a starfish and have had it for several year. I only wish I could tell everyone what kind it is as I do not know. Never seen one. Truth is never really looked. Got him at a reef show as it was closing as a bonus and thought oh he very cool looking and I am a pretty heavy feeder so ok. I need to take a pic of him and post it so maybe someone can ID him. He is reef safe and though I thought he would be a carnivore like a lot are. He is an omnivore or veg starfish. Not sue. He is hard kind of like a chocolate chip but thin. he has multi colors on him. Let me look online and see. Because Its one I would be more apt to suggest
Though I have not found a name yet it looks like this so I believe it one of the many Fromia species. Mine does have more colors but body shape and ECT is like this
http://www.liveaquaria.com/product/prod_display.cfm?c=497+528+2133&pcatid=2133
http://www.liveaquaria.com/product/prod_display.cfm?c=497+528+580&pcatid=580
So if someone really wants a starfish IMO this is the species to have. Then again what do I know and maybe I am just lucky with the one i have.