Esha Gastrpex
on Amazon
Not tried it myself, apparently shrimp safe though.
Ive actually not seen any snails recently (although I do still see tiny limpets). I decided not to worry about the snails, if they're in the tank and not massively increasing in population then they'll not do any harm, and will actually help move the substrate about underground
. Less available food = less snails. I wasn't over feeding my critters, but I now tend to not feed at all at weekends giving them a fasting period.