I have a Sta-Rite Hi-Rate Sand Filter, Model T 240 BP-1. It is no longer manufactured. The tank is leaking on the seam at the collar. I've tried AquaMend epoxy putty inside and out. It seems to be holding on the inside of the tank. But, on the outside of the tank, the water pressure is too strong and it leaks through the epoxy. Any ideas about how to repair the tank without purchasing a whole new filter system? Thanks.