Wow, Susan, really? I think that's probably far too much positive energy for the snails. Dont know if they can survive in these conditions. Sirdarksol is right, you need to hate them for them to thrive.
OK, seriously, though. What you'll need is loads of algae, so place your farm in direct sunlight if you can (but not somewhere your snails will cook in the baking heat, of course). Leave them a piece of lettuce and refresh it when it starts looking dodgy. Don't forget to REALLY thoroughly clean your lettuce or the snails might suffer from the pesticides on them. Also, you'd need to change 50% of your water like once a week or so. Oh, and they appreciate a calcium-based substrate, so if you could get your hand on some empty snail shells, they'll love you for it.
Yep, snails are there to frurstrate us, Amorinthe. I am convinced. You want them, they're gone. You don't want them, they multiply.
