pool leak detection & problems - fixing, finding a pool leak, leaking, leaky pool

Swimming pools can develop leaks as the result of routine wear and tear, carelessness, accidents or the effects of wintertime conditions. Not all loss of water can be attributed to a pool leak. Losses, due to evaporation, splash out or backwashing, are normal and are expected. Excessive water loss, more than 1/4"-1/2" daily, should definitely be investigated. Products are available to help determine if there is a pool leak, where the leak is located and to help seal the leak. There are companies that specialize in pool leak detection and repair. Clicking on the underlined and highlighted "keywords" or "catch phrases," in the archived answers will give you access to additional information on that topic or product. Please refer to the Glossary, if there are terms or phrases that require explanation.

More information about Fix A Leak can be found on the Marlig Industries, Inc. Preview Page in the "Pools & Equipment" Product Information Section. Links are available to connect you to their website. To order this product on-line, click here.

I have a sinking feeling that my inground pool has been losing water and mentioned it to a pool-owning-friend. He mentioned that there was an article about repairing a leak in a swimming pool, in the real estate section of the New York Times, around the end of July. Unfortunately, he did not keep the article and that weeks Times is off to the recycling plant. If possible, could you shed some light on what it said?

Basically, it went through some of the options. First make sure you have a leak and that the loss is not simply evaporation. This can be done with the bucket test. Place a 5-gallon plastic pail, on the first or second step, so that it is just a few inches above the water level, after being filled. Adjust the height, inside the bucket, to that of the pool and mark the level, both inside and outside. After 24 hours check. If the pool level is lower than the bucket level, you have a leak, that amounts to this difference. This technique cancels out the effect of evaporation. Where is the leak? If the return flow is aerated, most likely the leak is in the suction line. This type of leak stops, when the pump is running. You could plug up the skimmers, returns and main drain and see if the leak stops. If it stops, the leak is in the lines. If not, it is elsewhere. Rather than simply digging up all the lines, until the leak is found, call in a leak detection professional. They use special equipment to help locate the leak and simplify the repair. You could try using a concentrated dye solution to help detect a flow due to a leak. Divers can be used to hunt for a leak, using a dye solution. Different types of leaks and pools require different detection techniques and a leak professional may be the best way to approach the problem, especially when the water loss is more than 2 inches a day. For more information on leak detection professionals go to: www.poolleak.info The article mentioned that a pool owner can try to fix the leak themselves, simply by adding Fix A Leak. This product has been around for nearly thirty years and is worth trying, if the daily water loss is under two inches. For more information go to: www.fixaleak.com I hope that this information is helpful.

I have a 30,000 gal inground pool. I just got a new liner a filter and pump installed last week. I had got pressure testing done on my 1 return and 2 sections lines before this job as the pool is old that was normal. Now I am losing about 1/2 an inch of water every day , I also see a air bubble out of the return every 15 seconds or so when the filter is off. Could you please guide me in the correct direction as to what needs to be done. Is it certain that I have a leak? Thanks.

A 1/2" a day is about what you would expect to lose, if the pool was in hot, direc

t Sun and in a breezy, dry area. I suspect that you do have a leak, but the loss, is partially due to evaporation. If you would like to confirm the extent of the leak do this: place a plastic bucket with water on the top step of the pool, adjust the water level to that of the pool and mark the height of the water level, both in the bucket and in the pool. The next day determine the water loss in the pool and in the bucket. The loss in the bucket is due to evaporation. If the pool lost more, that portion is due to a leak. Usually, leaks in the suction lines show up as air leaks (aerated return flow), when the pump is running. If water is leaking out, air should not be bubbling in. This would also apply to the main drain line. I would check all of the seals, gaskets, o-rings and connections. There are dye solutions that can help you trace a leak. There are companies that specialize in leak detection. And there is Fix A Leak: a product that make a long-lasting seal small leaks. I hope that this information proves helpful.

There are products for leak detection. Your local pool supply retailer should carry a product like Anderson's LeakMaster Pre-Filled Dye Testers. The dye is put into a still pool, near places that may be leaking, such as light fixtures, returns, drains, skimmers and any visible cracks. If there is a leak, near the place where the dye is dripped, the dye will be sucked out at the point of the leak. Depending upon the type and location of the leak, it may be possible to add a leak sealer to the appropriate location. A leak sealer product, such as FIX A LEAK can create a long-lasting seal in walls, floors or the filtration system. Many times, a leak is either hard to find or massive enough, where do-it-yourself techniques may not be enough. There are companies that specialize in leak detection, using sound detection and other equipment or techniques. You can search a free directory of leak experts, in your area, at www.poolleak.info. Good luck and I hope that the information will prove helpful.

I have noticed that I must have a leak in my liner. How do I find this? Is there something I can put in the water that goes to the spot? I have an above ground pool 24' round. I would appreciate any suggestions.

You should try locating the leak with a leak-locating dye. Products like Anderson's LeakMaster Pre-Filled Dye Testers are available at local pool supply retailers. The dye is put into a still pool, near places that may be leaking If there is a leak, the dye will be sucked out at the point of the leak. Are you certain that the liner is the problem? Make sure, by checking all the lines and connections. If you allow the pool to leak, when the water reaches the level of the leak, it will stop. This can help you pinpoint the location the location. Once you locate the hole in the liner, repair is simple. Boxer Adhesives offers a line of underwater patches and repair kits that you can use to make a lasting repair. If you can't locate the liner leak, a leak detection company, such as Anderson Manufacturing, might be the next step. For more information and for dealer location information go to: www.poolleak.info They are designed to be applied under the water, so draining the pool will not be necessary. I hope that this information helps to solve the problem.

I am losing more than 1/2" daily from an above ground pool. The leak has to on the floor, but I can't find it. I have tried diving down and using a dye. I did have some pinhole from ants, but all have been patched. Any suggestions.

Possibly, there are some that are too small to be seen or are hidden from plain sight. Adding Fix A Leak can help seal these tiny pinholes. After being adding to the pool, the product should find its way to the pinhole. The seal can be very long lasting. Care should be taken to avoid vacuuming for at least two weeks. Otherwise, the pressure could suck out the material making the seal. Eventually, it will thoroughly cure and harden. If the leak is persistent and other methods fail, consider contacting a swimming pool leak professional. Leak experts, in your area, will use modern technology to find and fix your leak and can help avoid major damage and costly water loss. Search for a leak expert, in your area at: www.poolleak.info I hope that this information proves helpful.

I found your site on a search on Google and while I was searching for tips on fixing leak in the drain at the bottom the pool. Is there a way that I can do this myself or do I have to have outside help, you think? I appreciate any help you can offer. Thank You.

A main drain repair can be a big deal or a very big deal. It all depends on the problem and where it is located. Fix A Leak can be used to seal the leak, if it is not too large and it not subject to expansion. If it works, great! If not, you should consider hiring a pool leak expert. Major leaks can cause extensive damage to your pool, if left for too long. Go to www.poolleak.info, if you need to find a pool leak expert in your area. Good luck and I hope that I have been helpful.

My pool has been losing water over the winter months. I have been adding water to help prevent the cover from falling in. I feel sure that the main drain is involved. Is there anything I can do before springtime? Thanks for the help.

Adding Fix A Leak might just do the trick. To give the product a better chance of actually reaching the main drain area, you could pour the product down a length of 2" poly pipe. The product is much heavier than water and will sink down through the pipe. Just direct it close to the main drain. As the water leaks out, the product should find it way to the site. The repair could be very long-lasting! Look for the water losses to slow or stop, as a positive sign. If the leak fails to stop, it may be due to a cracked pipe and might need to be located and replaced. A professional leak detection service will use modern techniques to locate your leak and be able to perform the necessary repairs. You can find a qualified pool leak expert, in your area, at: www.poolleak.info Good luck.

I have an above ground pool and I have noticed 3 small tears in the lining at the water level. I patched them, but I am kind of concerned about avoiding trouble before it occurs. I believe it is due to age and a lot of snow this winter in NH. I was thinking of getting a new liner, but other than these tears and wear at the water line, it seems to be fine. I stumbled upon your site and found BorderLines and I was wondering, if this is just a cosmetic fix or would it also strengthen the liner at the water line and stop any leaks from occurring? The pool is about 8 years old. Thanks.

The problems that you are experiencing are the result of UV degradation, from the Sun's UV rays. These problems are usually worse on the sunny side of the pool. If you patch the existing damage and apply BorderLines around the pool, it will not only strengthen the existing liner, but will shield it from further damage for UV light. The product is warranted, by the manufacturer, for 3 seasons, at which time, it can be peeled off and another set applied, if you wanted to extend the liner's life even further. BorderLines will strengthen and cover up a faded or stained waterline area and create a whole new look. It can be used, equally well, on all sizes and shapes or vinyl liner above or inground pools. I hope that this information proves helpful.

Sincerely. Alan Schuster. 7/8/2008

I need to ask a question about my pool. I had a new liner put in two years ago because ants had gone under the pool liner. It is an above ground pool. I replaced the filter and chlorinator this past fall. So far the only thing not replaced has been the pump. I just lifted the tarp and the water level has gone down a lot since November. How can I tell if there is a leak? I cannot get too much help for my husband is 76 and medicine is taking a toll on my wages at work. I need to know a simple way to maybe detect it myself. Please advise me if you can. Thank you.

This does sound like a leak, as water loss should have been relatively small, unless t

he winter cover was not effectively sealing the pool. The only source of a leak would be the liner and is probably small. If there are no signs of puddling, the leak is probably on the pool floor. I suggest that you mark the current water level and seal the pool. Check again in a few weeks. If the water level is still dropping, the level is at or below the current height. If the water level did not drop, the leak is at the current level. There are leak detecting dye solutions that can be dropped into a still pool and can help pinpoint the source of the leak; allowing you to use a vinyl repair kit to repair the liner. The Boxer Adhesives line of repair products can even be used underwater, if necessary. If these efforts do not locate the leak, you might have to bring in a leak detection specialist. Good luck and I hope that this information proves helpful.

I have an air leak on the suction side of my inground pool. I was wondering if the Marlig leak sealer is appropriate. As I have two skimmers , I have been able to turn off one suction side and isolate it. I only need to add enough Fix A Leak to treat 70 feet of 1-1/2” i.d. line. I have the ability to pressurize this line to help force the sealant to the hole. Is there any benefit to this? Thank you.

Fix A Leak should work well to seal this kind of leak. By pass the filter and pour the product into the skimmer, where the suspect line attaches. Pressurizing the line can help. The leaking water needs to carry the product to the damaged spot. I hope that this will prove helpful.

We have a 10 year old inground pool with steel walls and a vinyl liner. The liner was replaced about 4 years ago. We currently lose about 2-3 inches of water every 2-3 days and have water that stands in the yard all through the summer. When prepping the pool for winter I allowed the leak to continue without adding water for several days. The water level receded below the skimmers, jets and continued for another couple of inches then stopped. I looked around the liner but could not find a hole. It also appears that the water level in the yard is resting at the same level of the pool water level. In the winter, the water in the yard dries up. I have suspected a leak in the main drain that stops once the water in the pool is even with the water level in the yard - possible? Any thoughts or suggestions?

Possible? Yes. If it is as you described and the return flow is not aerated, the leak should be in the main drain line or in the return lines, at the height where the leaking stops. If the return flow is aerated, the leak is in the suction lines and at the level of the standing water. Fix A Leak might help, as it can permanently seal a leak as big as 1/8" in diameter. The water loss indicates a sizable leak and you might consider a leak detection service. Anderson Manufactures makes high tech equipment to help locate a leak. For more information and for dealer locator information go to: www.poolleak.info This will help minimize the damage to the surrounding area. I hope that this information is helpful.

I just helped a buddy open his pool in NJ. Removed plugs from return lines, added our chemicals etc. We started the process 5 days ago and yesterday his pool DRAINED OUT in a matter of hours! He has no cracks in the gunite. Maybe his drain is broken, but somebody mentioned to him that a hydrostatic plug may be to blame. DID I DO SOMETHING WRONG TO HIS POOL? Don't even know what one is. Could something get stuck in it and drain it out? Why would it NOT be solely connected to the line back to the pump. Why would it be set up to also drain into the earth? Thank you.

Dave S., Parsippany, NJ, 5/11/2006

This valve is meant to protect the pool from popping up, if the ground water level gets too much higher than the pool level. It is not connected to the filter system. If ground water is too high, water may enter the pool, but water should not leak out. Possibly, the valve opened inappropriately. If the water table is high, the pool might not drain completely. The valve/drain might need to be replaced. More likely, there could be a major break in the main drain line. This is a serious problem. The main drain can be sealed off, but circulation will suffer and not having a hydrostatic pressure relief valve could allow the pool to pop up. As a means of improving circulation, you could add a robotic pool cleaner, which will act as a moving main drain. Otherwise, repairing the main drain line will require excavation. No, this was not your fault!

I have a 15' inflated ring above ground pool. I am quite sure that I have a leak in the bottom floor, since there is water coming out from under (not very much). My question is there a product that is safe to use on these type of pools? Will it damage the plastic liner/bottom? Your advice will be appreciated.

Karla H., 6/4/2005

P.S. WOW! This website is fantastic, your advice is so helpful, thank you!

This type of pool is made of thin walled vinyl. What you need to do is locate the leak. You can do this by adding a few drops of a concentrated dye solution (some dealers carry such a product) into a still pool. No filter running and no people! The dye should trace its way to the leak. Once you know where the leak it you can make a repair. Boxer Adhesives has just the product. Patches or tapes that are made to be used with thin vinyl pools and can be used underwater. Don't use a solvent based repair product, as it can severely damage this thin vinyl. For more information on these patches and tapes go to: www.boxeradhesives.com I hope that this information proves to be helpful.

I want to use the Fix a leak product. I have a small leak in my suction line (or I suspect). I don't understand the instructions that say to "reverse the flow of water at 5 or 10 psi". How is this accomplished? How do I reverse the flow of water so my out-take becomes my intake, etc? Thanks for your help.

When air gets sucked in, while the pump is running, it is necessary to reverse the flow. This helps the Fix A Leak exit the site of the leak and produce a seal. To reverse the flow, you must switch the hoses going in and out of the pump. Water will enter through the returns and exit through the skimmers. Make sure the filter is bypassed. After the leak has stopped, you can restore the system. Good luck and I hope that this information has been useful.

I was elated to find your site. We have a 12X24 concrete pool not quite 5 years old. We live in central Florida. My first question is related to the stains we are experiencing. They began as small light and dark grayish swirls in one small section of our pool. We went to our local pool supply store and they recommended a metal stain remover. It did nothing and since the stains are growing! They now cover most of the pool floor.

My second question is related to a possible leak. We seem to be losing about an inch of water per day. We thought it was due to the recent cold temperatures at night. However, it still seems like an awful lot of water to evaporate overnight. I've scanned the side tiles for leaks and used food coloring to determine if there were any leaks but nothing appeared. How can we determine if there may be a leak elsewhere, lines, etc? Also, what is the average amount of water loss we should be experiencing? Thanks very much for anticipated help.

Adding a metal treatment doesn't always work. You might have to lower the pH to approximately 6.0. Try this. Put about 1/2 pound of pH reducer powder in a white sock and drop onto a stained area. Leave in place for 15 minutes and then move around with the vacuum pole. If it works, the problem is definitely a metal. You can repeat elsewhere or use a stain removing accessory to siphon an acid solution onto the stains. Once removed, add another dose of the metal treatment. Thereafter, add monthly or whenever new water is added. Refer to the archives on "Pool Staining Problems" for more on the subject.

Finding a leak isn't always simple. One inch per day is likely to be a leak. Average water loss depends upon temperature, exposure, wind speed and other variables. A loss of 1/4"-1/2" per day would be more realistic. The leak could be in the main drain line or the skimmer lines. A leak in the return line, could create aeration in the pool, but not necessarily a leak. Try this. If you would like to confirm the extent of the leak do this: place a plastic bucket with water on the top step of the pool, adjust the water level to that of the pool and mark the height of the water level, both in the bucket and in the pool. The next day determine the water loss in the pool and in the bucket. The loss in the bucket is due to evaporation. If the pool lost more, that portion is due to a leak. Close off the skimmer lines at the multiport valve and plug up the skimmer intakes. If you are still losing water, the leak is not in the skimmer lines. If it stops, the leak is in the skimmer line. While there are companies that specialize in leak detection, you might want to consider using FIX-A-LEAK. Used as directed, this product can make long lasting seals, in leaks in the plumbing and even the walls, as large as 1/8" in diameter. It is not overly expensive and could solve the problem. Good luck and I hope that I have been helpful Let me know how it works out!

I have a 14 x 28 inground kidney shape cement pool and the pool loses about a 0.25 inch of water daily. I bought the house last year and had all the cement in the pool redone. The pool was built in 1975 and there is a ground drain at the bottom. The piping runs to my garage, where the pump, filter and heater are. The heater is very old: 1977, the pump is new and so is the filter. Do you think the cap at the bottom may be loose, so water is draining out? Let me know what you think.

A loss of 0.25" per day is not conclusively a leak. Given normal evaporation and splash out loses, that amount may be within normal expectations. Such a leak would be quite small. Any leak is somewhere below the level of the water and given the slowness, might take a considerable time to reach the level. If you would like to confirm the extent of the leak do this: place a plastic bucket with water on the top step of the pool, adjust the water level to that of the pool and mark the height of the water level, both in the bucket and in the pool. The next day determine the water loss in the pool and in the bucket. The loss in the bucket is due to evaporation. If the pool lost more, that portion is due to a leak. There are dye solutions that might help locate the leak. Fix A Leak might be able to seal the leak. For more information on this product, go to www.fixaleak.com If there is a leak and you fail in your efforts to seal or locate it, you should consider calling in a leak detection professional. For more information, on the service and dealer locations, go to: www.poolleak.info Good luck and I hope that I have helped point you in the right direction.

I have one of those pools with an inflatable top ring. Seems to have a leak and I am slowly losing air. Any suggestions about locating the leak and fixing it? I appreciate your time and effort.

Look for signs of bubbling, where the ring is covered with water. That will indicate the location. If you don't see bubbling, the leak is above the water level. Get some swimming pool algaecide that contains dimethyl ammonium chloride. Make a solution of one part algaecide and 3 parts water and stir it up with a 1-2" brush so that it lathers a bit. They use a technique like this to find a leak in a tire. You don't want to use soap, because you don't want it to end up in the pool water. Brush it on the seams and other areas, until you find the leak. Once found, clean the area with rubbing alcohol and allow to dry off. With this type of thin walled pool, you cannot use a traditional vinyl adhesive and patch, as this can damage the vinyl. Boxer Adhesives offers a complete line of vinyl repair products, including an adhesive patch that is intended to be used with pools just like yours. Visit them at www.boxeradhesives.com for more information. If necessary, it can even be used under water! I hope that this information will prove helpful.

► Finding A Pool Leak?

Alan, I have a pool that is leaking as much as three inches a day, and I'm confused about where the leak is located. I thought the multiport valve might be leaking into the backwash while in normal filtration position. After five hours of filtration the pool lost about 1/2 inch of water. The valve is very old and I thought this may be the cause of the leak. Then I did a drain down without running the filter. After two days the water level dropped to the base of the skimmer opening and stopped. However, when the water level is where it should be I can still vacuum. So, I'm not convinced that the skimmer has a suction leak. Any advice you could give would be appreciated. Thank you.

Stuart S., Boulder City, Nevada 3/15/2003

It would have been helpful to know what kind of pool this is: above ground or inground, gunite or vinyl. The problem is not the multiport valve because there would be evidence of water seepage that would be conclusive. My guess is that this is an inground pool: an above ground pool would have exposed lines and a leak is easier to find. The fact that the water level dropped to the skimmer base, means that the leak is due to a bad seal in the skimmer, a crack in the skimmer, a bad line connection at the skimmer or leak in the line from the skimmer to the filter. A leak in the return line would produce a lot of aeration, when the filter is in operation. The leak could also be from another point at the height of the skimmer base. I suggest that you do the following: Fill the pool up to the normal level and shut off the filter. Find a leak-detecting dye solution at a local pool professional store. Basically, it will direct you to drop some dye, into the still water, and look for evidence of a water flow. If there are steps, underwater lights or other through the wall items, you will have to check these as well. Sometimes, leaks are in inaccessible location such as underground lines. Frequently, it is possible to add a leak sealer compound to the pool or intakes and create a long-lasting repair, without costly excavations. FIX A LEAK has been used for this purpose with proven results. Look for the product at a pool professional. In addition, there are companies that specialize in leak detection, using specialized detection equipment, if your efforts prove unsuccessful. I hope that I have been helpful and good luck.

I noticed that the water was accumulating as winter neared on top of the winter cover. It froze near the top and then I noticed weekly it kept getting lower & lower. I am now trying to remove the water from the cover (this is an inground pool with a drain at the bottom) but as I take water from the top, it keeps lowering with inside the pool. I stopped taking water off (still have Lots more to go) and the winter cover is about 2 to 2-1/2 feet in the pool. It appeared when I stopped for the night and checked in the morning, the water level in the pool was still at the same level. Does this mean there is a leak in the pool. I closed with water level about 12 inches from the top, blew out all jets and sealed them. Do I continue to take all the water off the cover and check for leaks within the pool? Right now it looks like about 3 feet form the top of water is gone. It's a 19X32 kidney shaped inground. Liner is only 2-3 years old.

EJ, 3/31/2006

It appears to simply be a leak in the cover. You're pumping the water off the cover and it is coming from the pool. I suggest that you get as much of the debris off with a leave rack and then remove the cover. Try and find the hole and use a patch to make the repair. Boxer adhesives has the right product. Good luck with the clean up.

Hi Alan. Where can I buy the Fix A Leak product in the St. Louis, Missouri area? Thanks for the help.

For local dealer availability, call 905 374-2560. They might be able to provide you with the necessary information. Because their sales are mostly through distributors servicing the pool retailers and service companies, they might not have a location name available. You can order it conveniently online, from this website: Click Here. For product information go to: www.fixaleak.com It can be ordered from this website and will ship within 24 hours. I hope the information helps solve the problem.

We have an inground pool in Cape Coral FL. I replaced the pump recently. I just fixed a new leak on the solar panel and now find that I am also losing water at the returns on the pool wall. The dye gets sucked in at both returns when the pump is off. Most likely cause and fix? Thanks.

Chet B., Cape Coral, FL, 5/14/2008

Something loose or cracked? If you see the dye getting sucked in, you might solve the problem with Fix A Leak. Put some product into a squeeze bottle (like something used with condiments) and slowly squeeze product around the return. Pump off! The Fix A Leak will get sucked in and should make a seal. Confirm with the dye. If the leak stopped, leave off the pump for two days, in order to allow the product to cure. Clean or backwash filter after running for two days. I hope that this information is helpful.

Sincerely. Alan Schuster, 5/14/2008

I noticed my pool skimmer has a slight crack in it and I was losing water all last year. Is there some type of adhesive I can use to seal this crack or do I need to replace the whole skimmer?

Boxer Adhesives makes a line of repair kits and patches that you can use, including a skimmer repair kit. I hope that this information will prove to be useful.

Alan, I have a 25,000 gallon gunite inground pool. I recently bought the house and I am trying to figure out the water level. I have a skimmer and a main drain. Lately, when the pool pump turns on the morning it seems like the pool skimmer is pulling water faster than the water entering the skimmer can fill the basket. It eventually regulates it self or if I play around with the Float Valve assembly. Ironically, on two occasions I have added water for about 3 minutes and the skimmer flow regulates itself ( I would not think adding water for 3 minutes would add enough water to correct a low water level). It seems like the pool may have a low water level. I am worried I have a leak. p.s. The water level going into the skimmer is about an 1 inch over the entry to the skimmer. Thanks.