Zebra loaches - Botia striata - Like all loaches, they prefer the company of their own kind. I wouldn't stock with less than 4 or 5. I am not sure if that will overpopulate your tank. Their max size is about 4 inches. Mine LOVE snails!
I'd also recommend the zebra loaches and not the clown loach. However my top recommendation would be to try using snail traps.