I recently added some Odessa Barbs to a snail infested tank. They immediately devoured pretty much all the small snails, to my surprise over a few weeks they learned to eat all but the largest pond snails. I now have a tank with a bunch of pretty barbs, a substrate littered with snail shells, and a few snails hiding in the plants.
I'm generally happy to have snails in the tank, and I seem to have struck a lucky natural balance.
Anyway, my point was Odessa Barbs have been a surprisingly effective and attractive form of snail control.