I have replaced the Sand (925 lbs) in a Tr140. Removed the sand by removing the sand drain and backwashing. While removing the sand drain, I had stripped the threads on the sand drain part by not realizing it had reverse threads. The threads on the fiberglass tank look good, not striped out. So I replaced the striped out sand drain part, using pool grease on the o- ring and plumbers tape on the cap threads. Now I have drip at the 2.25 in nut where the o-ring is compressed againt the tank. Do not want to remove the sand. Should I just tighted a bit more? I have drained the water from the tank. Thinking about backing the fitting out far enoungh to wrap the threads with plumbers tape and adding some silicone. Afraid to remove complety, out of fear of notbeing able to push back thru 925 lbs of sand. Has anyone out there experienced something like this? Any tips?