I have been trying to correct a leak from my spa that was losing 2 inches of water every 12 hours - but stopping at tile line. Over the last year plus, I have takes the following steps (leak masked by autofill, but obvious because of declining chemical levels):
1) Let water drop with pump off and autofill off. Determined water levels drops rapidly to the end of skimmer / tile line, then stops (small evaporation only after that). Massive leak documented by falling salt levels in water (200 ppm / day while autofill runs). Pretty sure leak is not in the plumbing as pump joints now solid (replaced pump and PVC connections) and no water there. Further, leak happens with pump off. And repeating, leak stops at tile line / skimmer. Inside skimmer box, basket says full so source of leak is not the suction pipe to pump.
2) Have failed to find a leak using dye. Cannot find a spot where dye is sucked in. Biggest problem is that the skimmer joint with the pool is under a coping stone, and there is a long throat of diamondbrite at the bottom (I assume over gunite), with tiles on the sides, leading to the skimmer joint (all under the coping stone).
3) Spa was refinished this May. Joint with spa and skimmer was filled with fresh mortar so it should be water tight.
4) On skimmer side of joint, at the tip of the throat, the weir door was removed about 5 years ago by my former pool service company. I believe they cracked the lip of the skimmer as I saw remnants of a prior patch there.
5) I have tried several times to seal the lip of the skimmer with pool putty, in case it is leaking. None of this has helped. Tried last year multiple times and again last week. Leak remains at 200 ppm salt / day.
6) Yesterday I used epoxy to create a U shaped partial block on the diamondbrite / spa side just before water enters the skimmer. My goal was to isolate the leak on either the spa side or the skimmer side. I am looking to see which area loses more water (the U creates a 3/4 inch lip presumably that water does not cross over while water is still), and it looks to me like spa side has more water loss. I am attaching pictures. I continue to monitor hourly. It seems that the "normal" rapid water loss occurred overnight, but at 9 AM today I had lost 1.75 inches or water instead of the expected 2 inches. I would say its close enough that its probably artifact, except the rate of drop has now slowed significantly on both sides of the U. But it does look like water is falling on the blue side (spa) more than on the white side (skimmer) I am continuing to monitor, but its raining so that will set me back.
7) Thinking that the leak my be on the spa shell at the tile line and not inside the skimmer, I tapped on the spa tiles. The two tiles on one side of the throat under the coping stone going into the skimmer sound hollow, relative to the other time. Again it's difficult to say for sure as all of this is under my coping stone. But this is the first sign I have seen of something that might actually cause a leak. I just wish I could confirm with dye.
8) Looking back at old photos and trying to remember past experiences, my pool company has replaced the spa tiles at the skimmer area several times over the last 20 years. The outside tiles (not in the throat) have failen off at least on three separate occasions and been repaired. I do not recall anyone calling my attention to repair of the throat tile, but the diamondbrite at the bottom o the throat was redone about 4 years ago (company was fixing a crack in my pool and used the wrong color of diamondbrite so the patched areas stood out. I can see in old photos that they redid the throat section at the spa (it was much lighter, before this year's refinish of course) - this was all billed as "skimmer crack repair" along with the repair they made where the weir door came out.
Obviously I wish this was addressed properly before the season and before the spa and pool were refinished. But I am where I am. At minimum, I think the two hollow sounding tiles should be popped out and replaced (with the area waterproofed). But should I also remove and replace the coping stone above this area so it's easier to access? Also, I am not sure that the flat area in the throat with fresh diamondbrite is not leaking too. As I said, I believe this was leaking 4-5 years ago but repaired by prior service company (and they are not cooperative now in terms of telling me what they did or did not do - they refused to even acknowledge the leak last summer before I got rid of them).
Sorry lots here, but I wanted to provide as much detail as possible. I have invested many many hours in this project to date - it is very unpleasant having to add salt, calcium and stabilizer to the spa twice a week as part of the routine maintenance, not to mention the water is going somewhere and that can't be good (lots of ants in the area, probably attracted by the leak).
I might add I have been trying to get a pool professional over here to help me with the detection and repair, but its difficult to find someone in the area who I will not also give a weekly service assignment to. Regular customers get priority.
Photos below from last year and current. "2021 early repair" was from patch work done in 2017 or so.
1) Let water drop with pump off and autofill off. Determined water levels drops rapidly to the end of skimmer / tile line, then stops (small evaporation only after that). Massive leak documented by falling salt levels in water (200 ppm / day while autofill runs). Pretty sure leak is not in the plumbing as pump joints now solid (replaced pump and PVC connections) and no water there. Further, leak happens with pump off. And repeating, leak stops at tile line / skimmer. Inside skimmer box, basket says full so source of leak is not the suction pipe to pump.
2) Have failed to find a leak using dye. Cannot find a spot where dye is sucked in. Biggest problem is that the skimmer joint with the pool is under a coping stone, and there is a long throat of diamondbrite at the bottom (I assume over gunite), with tiles on the sides, leading to the skimmer joint (all under the coping stone).
3) Spa was refinished this May. Joint with spa and skimmer was filled with fresh mortar so it should be water tight.
4) On skimmer side of joint, at the tip of the throat, the weir door was removed about 5 years ago by my former pool service company. I believe they cracked the lip of the skimmer as I saw remnants of a prior patch there.
5) I have tried several times to seal the lip of the skimmer with pool putty, in case it is leaking. None of this has helped. Tried last year multiple times and again last week. Leak remains at 200 ppm salt / day.
6) Yesterday I used epoxy to create a U shaped partial block on the diamondbrite / spa side just before water enters the skimmer. My goal was to isolate the leak on either the spa side or the skimmer side. I am looking to see which area loses more water (the U creates a 3/4 inch lip presumably that water does not cross over while water is still), and it looks to me like spa side has more water loss. I am attaching pictures. I continue to monitor hourly. It seems that the "normal" rapid water loss occurred overnight, but at 9 AM today I had lost 1.75 inches or water instead of the expected 2 inches. I would say its close enough that its probably artifact, except the rate of drop has now slowed significantly on both sides of the U. But it does look like water is falling on the blue side (spa) more than on the white side (skimmer) I am continuing to monitor, but its raining so that will set me back.
7) Thinking that the leak my be on the spa shell at the tile line and not inside the skimmer, I tapped on the spa tiles. The two tiles on one side of the throat under the coping stone going into the skimmer sound hollow, relative to the other time. Again it's difficult to say for sure as all of this is under my coping stone. But this is the first sign I have seen of something that might actually cause a leak. I just wish I could confirm with dye.
8) Looking back at old photos and trying to remember past experiences, my pool company has replaced the spa tiles at the skimmer area several times over the last 20 years. The outside tiles (not in the throat) have failen off at least on three separate occasions and been repaired. I do not recall anyone calling my attention to repair of the throat tile, but the diamondbrite at the bottom o the throat was redone about 4 years ago (company was fixing a crack in my pool and used the wrong color of diamondbrite so the patched areas stood out. I can see in old photos that they redid the throat section at the spa (it was much lighter, before this year's refinish of course) - this was all billed as "skimmer crack repair" along with the repair they made where the weir door came out.
Obviously I wish this was addressed properly before the season and before the spa and pool were refinished. But I am where I am. At minimum, I think the two hollow sounding tiles should be popped out and replaced (with the area waterproofed). But should I also remove and replace the coping stone above this area so it's easier to access? Also, I am not sure that the flat area in the throat with fresh diamondbrite is not leaking too. As I said, I believe this was leaking 4-5 years ago but repaired by prior service company (and they are not cooperative now in terms of telling me what they did or did not do - they refused to even acknowledge the leak last summer before I got rid of them).
Sorry lots here, but I wanted to provide as much detail as possible. I have invested many many hours in this project to date - it is very unpleasant having to add salt, calcium and stabilizer to the spa twice a week as part of the routine maintenance, not to mention the water is going somewhere and that can't be good (lots of ants in the area, probably attracted by the leak).
I might add I have been trying to get a pool professional over here to help me with the detection and repair, but its difficult to find someone in the area who I will not also give a weekly service assignment to. Regular customers get priority.
Photos below from last year and current. "2021 early repair" was from patch work done in 2017 or so.
