I got a harlequin shrimp several months ago to take care of asterina starfish. It did a great job of eradicating them, so now I feed him a sand-sifting starfish when I see him looking for food. The problem is that Quin eats a whole sand sifter in just a few days. I don’t know how he does it, but he’s a chow hound. How often do I need to add a new sand sifter to keep him happy? Quin may turn into the most expensive thing in my tank with his appetite!