I am having a problem keeping Mexican Turbo Snails and Emerald Crabs in my tank. They will last for like two months and then die. There are 15 Regular Turbo Snails, 2 Nassarius Snails, 3 Bumble Bee Snails and 20 Small Blue Leg Hermits; they are fine and every thing else in the tank looks good. I have a BioCube 29. My params are normal. I can't figure it out. Could they be starving? I am at a loss. Any help or ideas on what is going on?