My snails started dieing last week. I have noticed my tank has been very clean the past month. I think they may be starving! I had about 15 turbo's and 10 trochus.55 g tank. I have lost 5 in the last week or so. Tested my water today and the nitrates are sky high. I will be doing some heavy water changes to get it down. Any other ideas why they are dieing? What supplementary food can I feed them? Thx.