Even if your fish do go to town on your snails, they probably won't knock out 30 snails at one time......Add them at night with the lights out so they can spread out and hide! Your Snails may be able to procreate fast enough to keep up with periodic losses....maybe not. If they can't keep up with the fish eating them, who cares....you got 30 fish who will work at your algae until they become free delicacies for your fish! What a bargain! That's what my idea was with adding Ghost Shrimp to my cichlid tank. They would go to town on them and kill every one they saw the first day (I added them in full daylight too). The few that would survive the first day would slowly be dwindled down to nothing.....the whole time cleaning up my substrate of extra food! Sometimes I'd find them when doing a serious tank cleaning.....several weeks later!
AWESOME deal!
AWESOME deal!