I've been trying to solve a leaky coupling on my hot tub's pump. The leaky coupling is above the pump (whereas the other connection on the pump runs to the heater, and is on the side of the pump). The other end of the leaking coupling goes to the filter (which is a pressurized filter container). The coupling has gradually been dripping more and more. I did a little research online, and most spa web sites recommend only to tighten these couplings hand tight, so I didn't want to over-do it and create a bigger problem.
I unscrewed the coupling, and saw there was a silicone-looking washer, but there did not appear to be any kind of washer or o-ring on the underside of the coupling.
Based on a recommendation from a local pool & spa supply store, who said their pool guys use liquid Teflon-based thread sealant, I picked up some "Rectorseal T plus 2". I cleaned off most of the old (caulk-like?) sealant from the thread, then gooped on some Teflon sealant, tightened everything up, filled the tub, and plugged it in. I was dismayed to discover the coupling was leaking worse than before I messed with it!
What did I do wrong? Any suggestions for fixing this leaky coupling? Do I need to replace the washer and/or coupling? Add an o-ring inside the coupling?