I also have some snails that hitch-hiked in with live plants, don't know latin name for them, but most people know what you mean if you say they are pond snails. I have live plants in nearly all of my tanks, so the snails have spread with the plants and are in most of my tanks too. I don't think it is that big of a deal. The snails scavenge for food scraps; if you don't overfeed, there won't be an abundant food supply, and they won't breed as fast. However, you will eventually get a good supply of them, and whenever this happens all I do is crush a few. There are very few fish that won't appreciate a fresh escargot snack now and then.