If you actually want to encourage snail reproduction, you need to look for specific species. Most are what refered to as spawn scatterers. Meaning, they release their reproductive materials into the water column and what comes of it is usually coral/filter food. The equipment (powerheads, skimmer etc) either destroy or remove them before they can mature and move on from their planktonic stage. Unless you have access to a kreisel tank, your success will be next to nil.
By far, your best option is going to be egg layers, specifically strombus species. Most do not have a planktonic stage and the best chance for success.