water level dropping

HELP! I have a new liner pool (in ground 20x40) put in last summer. I have lost about 1-2 inches a day lately and at first I thought it was lots of kids in and out, but now it seems too much. I have turned the filter off to see how low it will go this morning. I dropped a little dye around all of the inlets and skimmers, but all I had to use was food coloring and it was the gell type and too heavy I think. I didn't see any obvious sucking in of the dye, but it probably wasn't reliable. How to you do a dye test for the bottom drain and what kind of dye is the best to use. I am also leaving town for a week next Sat and am worried about how to leave it if it is not fixed.. HELP! I have loved using bleach this summer, it has been so easy!!!

On a 20x40 1 inch relates to about 500 gallons a day. That's a lot. For dye, someone on the forum recommended RIT the fabric dye. Obviously diluted. You can go to a dive shop and get a dye marker and break it apart and make dye from that. I have suggested but never used myself, beets. Get a raw beet, chop it up, boil, get a deep red dye and eat the beet. Do you notice a difference in leak rate with the pump on or off? I'd recommend making precise depth or level measurements. Could be something as simple as a ruler against the skimmer or other known point of reference. Leak rate measurements may be a clue as to the depth of the leak because as the water level approaches the leak level, the leak rate slows. As for injecting dye, for the deep areas I used a 10' piece of 1/2" PVC pipe with a small diameter auto vacuum line hose taped to it so I could squirt from a 1 gallon garden sprayer filled with the dye. You have to squirt just a little and very slowly to minimize the effect of water currents. Duct tape and silicone seal can be the adapter between the hose and garden sprayer nozzle. As for leaving it for a week...big IF. At 1" a day, no problem. 2" a day could be 14"...should still be no problem other than the water loss.
Best I can do for now.
Al

Thanks for the info. I did get food coloring from the store and did not find any leaks this am at any of the inlets or skimmer. The pool guy says it is probably a hole in the liner, which I guess would be better than a pipe leak if we can find it. Any suggestions on the best way to do that???? I will try the pvc pipe to get the dye to the bottom drain tomorrow. And the measuring the loss with a ruler - I will start a chart for that too. I did put a piece of tape, but decided to add water so that is not good anymore. the ruler is easy. Thanks for that idea! Any tips on how to find a hole in the liner would be great. Thanks

I know that one method is to just let the water drain and see where it stops. That could be dangerous if it is at the bottom though. Did you check all of the seems and corners with the die? I think that this is all that a leak finder will do is scuba around and die test.
This is all assuming that the leak is in the liner, how many returns and skimmers do you have? do you have a way to isolate any of them?

Hi Carolyn,
Since the liner is only a year old I guess it's possible a seam opened. Chasing my leak last year, a pool contractor told me that if a seam is going to open it will do it usually in the first couple years. Someone else may kick in other thoughts on this. I next started with the dye around the junction of the floor and sides at the deep end. Had already figured it was a deep end leak because the leak rate didn't change as the level dropped. Have to go very slow with the dye. Position the hose, squirt a little, and wait a little. I was losing about 3 quarts a minute and when I hit the spot it was obvious. Found it within an hour. 3 small slits inside a 2" diameter circle maybe caused by agressive use of the pool vacuum brush. You also need the water to be really still, no currents to disperse the dye. To see how difficult finding a leak of this size I stuck a garden hose on the bottom and started a siphon and set the rate to be my 3 quarts per minute. Then was able to see what to look for with the dye. Funny thing, with the naked eye I never saw the slits, until I knew where to look.
Hope this helps a little more.
Al

AL, did you ever swim around the bottom with a mask and look for the leak? That is what I was told to do at the pool store. Also, did you use the RIT dye? I am going to get my husbands help on the pipe contraption to get the dye to the bottom. Some one could probably make a fortune selling something to find the leaks! Thanks for your help.

I didn't go down and look. Water was way too cold in April. I scarfed some dye tablets years ago that are used for stream tracing and other things. One tablet makes a good gallon of red fluorescent dye. Someone else on the forum suggested the RIT. My water was extremely clear while chasing the leak...that's a necessity. Found a slick way to lay a deep end patch too. Post #9 in this thread
http://www.poolforum.com/pf2/showthread.php?t=101

Al

Block off the skimmers and see if it still leaks with the pump shut down, if it does then it is most likely the liner or main drain. If it does not it is either a leak in the skimmer, the return lines or the feed lines. Close one off at a time and run the pump for 24 hours and see which one causes the water to drop. I recently had a problem like this and found it was the pressure line feeding my polaris that had a crack in it under ground.

OK, We had a big rain storm last night so all my measurements are wrong on isolating each pipe. I'll start that again. At least I got some free water !
Al, Do you have a picture of the red dye contraption you made?? Your pics on the link for the patch were very helpful!
Thanks everyone for all the info, It is such a help to be able to find help!

Carolyn,
I don't have any pics of that thing but I could take some. Tied up today so maybe tomorrow I'll do it. Considering the cost factors of finding the leak, fixing it, etc I just bought a $20 1 gallon sprayer at Home Depot or someplace dedicated to this leak finding task. For the vacuum line hose attachment you can blob silicone seal to the sprayer thing and let it cure for a day. I always keep a few caulking size tubes of that stuff around. Also, I never worried about the dye staining the liner. Seems like it might but never had a problem because it disperses relatively fast and the chlorine will get rid of the color.
Al

STILL Need HELP! We did get something to work to get the dye to the bottom, Thanks, Al. I have put dye at all of the skimmers and inlets, all around the seams where the wall meets the bottom, and the bottom drain. with nothing that I can tell is leaking. I have taken measurements and seem to be losing about 1 1/2 inches a day, seems to be the same with the motor on or off. This seems like a lot to me, and that it should be pretty obvious when the dye gets close, Am I right? The filter and motor are 2 feet higher than the deck of the pool and I am not loosing the pressure in the filter, if that makes any difference. I am going to turn the filter on with just the bottom drain now and see what happens. My next ????? is Where is the next most likely place to be leaking and what else can I do??? HELP!

That rate of 1.5" a day is about 2 quarts per minute so that should be detectable if it's a single leak. I'm wondering about that bottom drain. If it's leaking out of a pipe then you probably won't find it with dye unless you can inject at the pipe opening somehow. Don't have one, never saw one apart, so don't know if getting to the pipe is possible.

Anybody out there know about this?

There are companies that use electronic leak detectors to find pinhole leaks in liners. Not sure exactly how they work but they rely on the leak forming a conductive path between the water in the pool and the outside world.
Only other suggestion I have is to let it drain and every 6 hours or so make as precise a depth measurement as possible and see if the leak rate changes. I let mine drop about 1 foot I believe, and in my case the rate didn't change so I figured it was a deep end leak. As the water level drops and approaches the leak you should see a decrease in leak rate. This can give you an idea if it's at the shallow or deep end and at least may narrow the search some.

Unfortunately I'm out of more ideas at this point.
Al

Do you have a light in the pool? I have heard that vinyl liner pools often leak around the lights. Might be worth trying a dye test there.

~Rick~

Well, I gave up and called someone to find it. It was a liner leak in the corner of the deep end where the wall meets the bottom. He even pointed it out in the first few minutes without getting in the pool! It was very obvious even to me. I guess we just missed it, or I really wasn't sure what I was looking for. Cost $225!!! but, I think I really liked him, And would use him again for anything we couldn't do ourselves. He looked over everything else while he was there and didn't find any other leaks, seams were good, and everything else is in great shape. He thought my PH was a little off and asked if I use CHlorine. I said yes--- well I do, but I just didn't want to say it was Bleach. He tested my chemicals and said everything was PERFECT! Couldn't be any better. Of Course I knew that. He told me Sams has a 100lb bucket of granular 99 % chlorine with no added fillers for about $100-- $1 / lb. Sounds good, but I am sure bleach is still cheaper and I am sold on the bleach method.
Thanks for all the help, and now I have my dye contraption all ready for the next time.

Glad it is fixed. Now, time to get in that pool and enjoy!

Carolynn,
Glad the problem is fixed. Bet you learned a lot in the process like I did. Next times are always easier. $225 doesn't sound bad at all. Just for our education I'm curious how he laid the patch.
Al

Oh no, I missed how he put in the patch!!! I had a tree guy there at the same time to take out a tree that died and could fall into the pool if it fell. He just happened to show up at the same time. All I know about the patch was that he used a piece of the left over liner cut out of the steps to patch the hole. Now, if I get another hole, what do I do??? That is if I can find it the next time. Oh well, I am out of town now, and the people at home tell me the pool looks great, no water loss at all! They are putting bleach in as scheduled!!! Thanks everyone for your help. I love this site!