A sand sifter I bought over a year ago and never see recommended is deer cowrie. I bought 2 from SWF and hadn't seen them until a week or so ago. They keep the DSB totally clean. I thought it was the hermits. When I put chopped shrimp in the tank, a couple pieces fell on the sand and it looked like the movie Tremors. I was wondering, "What the heck?" Then up came one cowrie. I looked behind the LR and there was the other one grabbing another piece. They were 3/4" when I bought them and now they're close to 3".