Slight leak at screw fitting on sand filter


Silver Supporter
Apr 12, 2015
Mississauga, ON, Canada
Hi Folks,

Looking for some advice on a small leak.
I replaced my filter last year, and am seeing a small leak (1 drip every few seconds) from the screw-in connections as shown in the picture.
I used a reasonable amount of teflon tape, though it seems the screw-in fitting went all the way in with out too much trouble.

Should I back it out and just add more teflon to assist with the seal?

IMG_1700 (1).jpg

Thanks very much


Gold Supporter
Jul 3, 2018
I would recommend replumbing both of those. Use unions that can be screwed in so that the o ring seals any leaks.
I agree. CMP Unions on anything that might need to be repaired or replaced (Pumps, multi-port valves, etc).
Threads: My own experiences have led me to use a combination of 1. Teflon Tape and 2. RectorSeal Premium Grade "T plus 2" Pipe Thread Sealant (magic stuff).
Not "too much" teflon tape, but the T plus 2 can be liberally applied (it squirts out and makes a mess, but you want it in there good. Just have a rag handy). For pipe diameters up to 1 1/4", apply to male threads only. Greater than 1 1/4", apply to both male and female threads.
Last edited:


TFP Guide
May 10, 2017
Hays, Kansas
It will self seal after a few weeks if you leave it alone.

Thread sealed connections are a pita sometimes.

If you wish to fix it just remember, if it has to be really tight your do something wrong.

Unscrew and screw it in a few times, this smooths out the micro cracks in the threads that the Teflon fills up. Remove it and re tape. Have the fitting looking at you and run the tape clockwise getting 3 layers for cheap normal tape and 2 for blue Teflon.


Silver Supporter
Apr 12, 2015
Mississauga, ON, Canada
Thanks for the suggestions everyone.

This was installed mid-last year, and I decided to leave it to the end of of the season, but now it's going to have to happen at the beginning of this one ;)
I'll give the pipe dope/teflon tape combo a try.