Leak... its somewhere in the liner, not in the plumbing

[caliskier]

Hi,

I have been perplexed about a leak my pool has had for some time. We have a gunnite hot tub and liner pool.

1. Did the bucket test on both pool and hot tub everything running to verify a leak, in 30 hours we lost 1.75 to 2 inches. Conclusion: Leak!
2. Did the bucket test on just the pool, draining the hot tub down below the returns, same results. Conclusion: Hot tub not leaking
3. Did the bucket test on just the pool, drain cover removed, drain pipe plugged with one of Leslie's stoppers, all returns plugged with winterizing threaded plugs with Teflon tape and rubber o-ring, both skimmers plugged with gizmos with Teflon tape. Conclusion: Plumbing is OK.

This is where I am at, I can already tell based on the last 5 hours that I am still losing water at about the same rate that I was losing it before, so tomorrow evening I expect to be down about 1.75 to 2 inches.

I have done the following tests (before I even started step one above)

1. Pump off, dye test, dropped in from outside the pool, above and in front of all items attached to the pool liner, i.e. skimmers, rope hook, returns, light. Dye did not seem to move at all
2. Took the light off dye in the light socket, very hard to tell if it was moving as I could not hold breath long, but seamed to be OK.
3. Have fixed 5 holes that I could find on the bottom of the pool over the summer. Last fix was probably 4 weeks ago, 3 of these were hard to find.
4. Main drain lid removed for plug, but looks OK, no cracks, dye did not seam to trace anywhere

What else I know, or think I know...

1. Last season we were new at this but remember thinking we seemed to be adding lots of water, but after we winterized the pool, (water below skimmers and rope hook, but above returns and light) it seemed to hold its water all winter.
2. I am 80% sure there are no more holes, but I really need to wear contacts (I wear glasses and can't wear glasses when I am swimming) when I snorkel and search the bottom.

So... Looking for recommendations on what I could be doing wrong, or where I should look next or whatever... Getting ready to close the pool in a week or so anyway.

 

[domct203]

Have you considered to let the water level just settle off? That will put the leak at or very near the new waterline.

Seeing that you did not lose water over winter I would be safe to say there are no leaks below that water level.

Dom

 

[caliskier]

Have you considered to let the water level just settle off? That will put the leak at or very near the new waterline.

Seeing that you did not lose water over winter I would be safe to say there are no leaks below that water level.

Dom

This is not a bad idea... I was thinking about lowering it below the skimmers to see if it stops, and then lowering below the light to see if it stops, etc. I was worried about keeping it chlorinated and cycled, But yeah, I can run it off the main drain and returns and shut off the skimmers and see how low it goes, just let it ride until it stops or until it goes below the returns.

 

[caliskier]

Found it! If it were a snake it would have bit me. The side of the pool near the return were I used to load my chlorine and then sweep the sides to mix, the corner is about 2.5 feet away from that return, the liner rated sweep brush must have punctured a hole in it, actually, 3 holes. I have patched them all, together I would say they made a dime sized hole. So, doing another test to see if this is the whole problem.