I seem to suddenly have hundreds of the little suckers all over my tank. Can't flush them down the toilet, or toss them out, and they grew so fast some are now pea to marble size, so how can I kill them? Gave as many as I could to friends, petstores don't want them, and i can't crush them because they bled all over when I tried, (ewww). or shells won't break. I have a bunch in a bucket for now, but no idea how to kill them. Any ideas? Anybody want some?