I'd say the best option is to go to your LFS and buy a few plants that have those small snails on them, I call them termites. They can clog up your filter if left to go out of control, but I have found they really help your plants and algae problems, and if you can get them big enough to have babies of their own, which isn't very big, then they'll produce so many that they can make enough survive.
Just my opinion.
--Jimmy