Originally posted by puffer32
Is there a star fish that doesn't deplete sand bed?
Yes, quite a few. Only the sand sifter star specifically eats infauna.
However, the others, such as Linckia, have VERY SPECIFIC NEEDS, and should not be purchased, or suggested, without lots of research and background info. Too many of these stars die of starvation in inappropriate (small, immature, non reef) systems.
Chocolate chip, general and red african stars are predatory, and can be fed more easily, and kept in more diverse systems. Same is true of many brittlestars.