[fintstone]

I have never used a gas detector. The way I troubleshoot something like this (hard to locate gas leak) is to turn off the gas source, clear the air a bit and the turn it back on...then immediately run a lighted match or lighter around the hose. A small leak acts like an orifice and you get a tiny pinpoint flame where the leak is. Then extinguish the flame, turn off the source and fix. Best if you have a helper to turn the gas on and off. That is the old fashioned way...just don't do it without clearing the air of gas for a few minutes first.

With the white paste pipe dope, you do not usually have to tighten quite so much so less chance of deforming fittings.