Help in finding a leak in my liner

[NHDad]

Hi,

I have an above ground pool that has a small leak in the liner (about 1/4 inch per day or so). I know this 'could' be evaporation but it continued to leak last year after I closed and covered the pool down about 1 foot below my return then stopped. So, I know the level of the leak (I measured it and wrote it down when I opened the pool this spring). There are no lights, drains, etc so it has to be in the liner and at the level I measured.

Before topping off the pool this spring, I got in with my waders and went around the pool twice inspecting the liner 2 inches above and 2 inches below the water line. I found one spot that seemed to have some bubble when I pushed on the liner but it was hard to tell if it was from my hand in the water. I patched it anyway, just to be sure. Now that the pool is operating and clean, I am still seeing the same water loss. I do need to measure with the bucket test but I can see loss overnight so there shouldn't be much evaporation.

I've searched the forum but haven't seen a lot of detail on leak detection related to my particular situation. It is usually around lights, drains, etc. I can easily do the food coloring test by my patch and by the single seam in the side of the pool but is there any other advice on finding a tiny hole? Does it make sense to try the food coloring around the entire circumference of my 24 foot pool at the level the water leaked to last fall? I imagine the hole is a pin hole so I'm not sure how well the food coloring will work.

One last thing... it seems to leak faster with the pump off than with it on. It didn't go down as fast when I was running my pump 24/7 to get through other issues.

Thanks,
-Eric

 

[Bama Rambler]

The best thing to do is run the bucket test. ¼" per day is perfectly attributable to evaporation.

but I can see loss overnight so there shouldn't be much evaporation.

Don't be fooled by thinking that evaporation isn't as bad overnight. I can go out to our pool at night and see a fog rising off it because of the difference in the water and air temp. In fact sometimes it evaporates faster at night than during the day.

 

[NHDad]

Thanks for the quick reply. I'll do the bucket test and post my findings.

 

[NHDad]

I did the bucket test and was losing 1/8 - 3/16 per day more in the pool than in the bucket. That was with both the skimmer and return plugged which isolated the pump/filter system. I spent over an hour in the pool yesterday with a snorkel and food coloring in a syringe testing around the level where the water dropped to last winter after covering the pool which I believe should be the level of the leak. I had no luck so I called a leak detection service today. I am going with one who does it electronically. I did call another place that told me it was no big deal if it wasn't leaking 5 - 6 inches overnight and that it dropped last fall after I covered it because I should have been pumping water from the top of the cover to the bottom of the cover all winter and it dropped a foot in a month or so because of evaporation through the cover. I quickly decided not to bother asking him about purchasing a new pump for my pool.

In other news, I did the Ascorbic Acid treatment 1 1/2 weeks ago. The water turned cloudy about 6 days into it with the heat and humidity so I increased the chlorine level to get the clouds out although the process warned against it. Bad move. The water is now green and staining again. So, I dropped the chlorine, made sure the PH is at 7.2 and added a quart of sequestrant with no luck. Still turning greenish. I was going to add more ascorbic acid last night and when I shut my pump motor off to switch the valve to recirc, it didn't start back up, just hummed. After reading the site, it looks like a capacitor issue but I cannot find the capacitor on my Pentair motor. It isn't attached to the side and isn't behind the back cover plate. So... I'm going to bag the whole pump motor thing and just buy a new pump today at lunch so I can do the ascorbic acid tonight.

 

[Bama Rambler]

Hopefully they'll find and fix it.

Bummer about your pump. Have you considered a 2-speed pump, or just a motor replacement?

 

[NHDad]

I did consider a motor replacement but my biggest problem is time and I can get a whole pump for about the price it would cost to have someone swap the motor. I would swap it myself but with my luck I'd find out at about 9:00 tonight that I need some other part to go with it and no place would be open.

I didn't give much thought to a 2-speed pump. Is there a big advantage for that?

Thanks,
-Eric