I bought levamisole and added 4ppm to the water and made it dark. The next morning I saw 3 or 4 worms hanging out his butt by a lot, but I think I saw one moving and the snails weren't dead so I added 4ppm more. How much does it take to stop them from moving?? I haven't seen any more of the worms move but my snails are still alive. And can I take out some of the worms with tweezers or something to help my fish pass them because there are so many I don't think he can get them out by himself.