Up until last weekend I had an overabundance of snails in my tank.
I got a few of them from a friend of mine, who was having trouble keeping their numbers down in her 5 gallon. They actually started to become a bit of a problem with me, until I picked up a pair of spotted puffers.
Immediately they took to the anemone that the snails had taken over, picking them off one by one. By the next morning, I couldn't find a single snail in my aquarium at all.