These snails do proliferate like crazy. You can just squash them on the glass and your guppies will eat them. Or pick a bunch out and sell them on Ebay. Mine used to only come out at night and kept the glass spotless so I didn't mind them. They never ate my plants. If you keep you glass clean of algae they will naturally lower their numbers. But picking them out is about the best way. Some people use a snail killer chemical. I have never tried that, just don't like adding stuff to my water.
And I agree with BoredAgain - I will be setting my tank back up in a couple months and will need to get more of these guys also.
And I agree with BoredAgain - I will be setting my tank back up in a couple months and will need to get more of these guys also.