I experimented with live plants about a year ago and my 20 gallon long has been a nightmare ever since. Pest snails have completely (thousands - no exaggeration) overrun the tank and my fish are doing bad because of it. I have tried removing them using the cucumber thing, manually crushing, assassin snails - and these buggers are still here. So I have removed all my fish from that tank (to other tanks) and I want to know how to kill the snails that are in their now. I want to kill every single one, and preferably have the tank still okay for use not too long after. So, is their a chemical I can buy? Is there anything I can do? Or do I have to drain the tank and start over with this one? I appreciate any responses to make this snail nightmare end.