If you want to kill them do it the old fashioned way. Remove the rock, or whatever it is they are attached to, they will retract, but you will see a hard tube looking think around the rock. Chisel it, pry it with plyers, whatever works for you. Don't allow this stuff to go into the tank. Then, rinse the rock off in water (from the tank but in a bucket outside the tank), to remove anything you might have left. Place it back in the tank, monitor and repeat. Best to do this before you get corals, because moving things in the tank is hard after that point. |