I have a Hayward pump for my Above Ground Pool. I just noticed that water is slowly leaking from around the pump housing where the tube goes from the pump to the filter. It is leaking around the plastic nut. I noticed that the sealant (white in color) is broken down and I had to tighten the nut tight to the base. Should I be replacing the sealant around the threads? If so, what kind of sealant is that? Plumbers putty? Wondering what that is. Can I damage by continuing tightening it? I hate to keep on it. Any thoughts? Thanks.