I'm about to go grab some duct tape velcro and sponge-like things to octo proof the rest of my tank and ran into some snags. Any suggestions on an easy way to octo proof an over flow? and seal up the back of the tank near the return line?
Get some PVC that's the same diameter as your overflow standpipe. Drill it full of 1/8th inch holes (takes forever). Pop it in the down turned side of the standpipe, pop an end cap on it. Wa-la, rigid strainer.