Your Complete Guide to Fixing a Pool Leak

Pool leaks can be grating, especially when you don’t know where the leak is coming from. While it is normal for swimming pools to get marred from time to time, that doesn’t make fixing pool leaks any less of a hassle.

This article shares everything you need to know about pool leaks. From identifying pool leaks to fixing them, learn here how to get your swimming pool back in tip-top shape again.

Swimming pools naturally lose some water due to evaporation or splash-out. However, you might find the level of your pool losing more than one inch every week. If that’s the case, then you may have a leak that is worth spending some time and money to repair.

Pools can leak through fittings or accessories, plumbing, or shell. It is important to pay attention to pool leaks to save water, heat, and chemicals. Controlling pool leaks can also prevent any future damage to your pool’s structural components.To learn more about the price of pool leak detection, click here.

There are easy steps to repairing pool leaks. But if you can’t take care of the problem yourself, you can hire a well-equipped pool professional in Florida who can do it for you.

Read on to learn more about identifying and repairing pool leaks.

Pool water evaporation

An experienced pool professional knows that pool water loss is not always a result of hidden structural damages. Sometimes, pool water loss is just a result of evaporation. That is why in any leak testing, the first step is always figuring out if the pool is actually leaking.

Sometimes, a surprising amount of water loss may be mistaken for pool leaks. However, the water loss might be evaporation caused by too much heat due to weather. If you are a new pool owner, then you may not be familiar yet with evaporation rates or what to consider as normal evaporation rates for a pool.

How much water your pool loses to evaporation is unique to your pool. Several factors can affect your pool’s evaporation rate. Such factors include location, ambient temperature, water temperature, crosswinds, and direct sunlight. Whether or not you use a solar blanket cover at night may also affect your pool water loss.

If you are living in Florida, then you can expect your swimming pool to lose about 1/16 to ¼ inch of water a day. In other areas, evaporation rates may be lower or even higher. To determine if your pool is leaking or if it is just losing water to evaporation, you need to conduct a bucket test.

Conducting a bucket test before anything else is so important in the pool leak detection process because it removes all the external factors that make your evaporation rates unique. Through this test, you will be able to measure the rate of your pool water loss versus the rate of evaporation in your pool.

If you suspect a leak in your pool, the bucket test is the first test that you need to do. If you keep getting inconclusive results with your test, then something as simple as identifying the temperature from one day to the next will help you get and interpret more accurate results from your tests.

How to conduct the bucket test

  1. Fill a 5-gallon bucket with water from your pool, leaving the water inside the bucket 2” down from the top. This water has the same temperature as the water in your pool and the bucket has enough water in it that it will be heavy enough so it will not float on the water of the pool.
  2. Turn the pool pump OFF and mark the level of the water inside the bucket using a piece of masking tape (painter tape).
  3. Mark the level of the water inside the pool (mark it on the waterline tiles near the skimmer) using another piece of tape. 
  4. After 24 hours, check the water level inside the bucket compared to the tape that was placed inside the day before (that is the evaporation). 
  5. Check the water level in the pool compared to the tape that was placed on the waterline tile the day before. 

If you conduct the bucket test and the water lost in your pool always matches the water lost in the bucket, then you can conclude that your pool does not have any leak and that your pool water loss is just a result of evaporation. If you use a solar blanket at night to cover your pool, expect your pool water to dramatically decrease due to water evaporation.


When you conduct the bucket test, it is best to record the weather patterns during that particular time period. These patterns include the outside temperature during the day and during the night, as well as the cloud cover and the amount of wind that you have. You also need to note if it rained or not, as rain may invalidate your bucket test results.

Pool leak detection

Leak detection is one of the most highly specialized branches of the pool industry. Building a swimming pool in Florida can be an easy task with the help of pool builders. However, maintaining it is often a difficult task for homeowners like you. This is why pool leak detection is one of the most searched subjects with regard to swimming pools.

A leak in your swimming pool can give you headaches. It could mean an increase in your water bills, excessive chemical usage, and even structural damage. Finding and repairing pool leaks is also time-consuming. This is because pool leaks are hard to find.

Swimming pools are meant to be watertight. However, there comes a time when sealants deteriorate while other parts of your pool shift and settle, or simply wear out. There are several subtle symptoms that your pool is leaking in a specific spot, and you need to be mindful of them. Often, you may not even notice something minor that a more experienced eye can see. Taking time to check these out can help you if you suspect a leak in your pool. 

  •         Is your pool only losing water when the equipment is on?

If that is the case, then it may be a pressure-side return leak. When the filter pump of your pool is on, the plumbing on the pressure side experiences pressure. This pressure causes small drips to open up into spraying gushers.

To remedy this, you can try checking the waste or backwash line of your pool to see if the water is running. You can also look for weepers where an underground leakage may surface. Check if there are soft or wet spots in your yard or somewhere on the side of your swimming pool, where the plumbing system returns water to the pool.

  •         Is your pool losing water only when the equipment is off?

If yes, then the leak could be a suction-side leak, which means that the leak is somewhere on the pipes that bring water from your pool. When the filter pump is on, the plumbing on this side of your pool is under vacuum so air is drawn in through otherwise leaking voids. You know it’s a suction-side leak if there is air in the pump basket, air bubbling out of the return lines, or air that builds up inside the filter tank.

  •         Is your pool leaking all the time?

Just because your pool is leaking all the time doesn’t necessarily mean that the leaks are coming from the plumbing. However, you can turn a suspicious eye on your pool shell and look for cracks in the plaster. Check the tile line and inspect the inside of your skimmers. Commonly, leaks emerge from the separation between the plastic skimmer and the concrete pool.

If you notice something that looks like a crack in this area, you can either use a pool putty to fix the leak or drop some test dye near it with the pump shut off. Underwater lights also help detect leaks, especially the conduit that runs from the light niche to the junction box.

Does your inground pool have a crack? Check out these 5 effective ways to fix a crack in your inground pool for you.

  •         Do you notice leaks at the equipment pad?

When identifying possible leaks, it also helps to look closely at the filter, pump, heater, and valves. You can also turn the pump on and off and see if there’s spraying water when the pump is turned off. A tiny drip will not be the source of the leak, but if water loss is noticeable in the pool, there should be a trickle at least.

  •         Does the water even out at a specific level?

Close the skimmer valve and let the water level drop below the skimmer while running the pump on the main drain. If you notice that the water still drops, you can easily rule out the skimmer.

However, if the water stabilizes at a certain level, conduct a dye test and check around your pool very carefully, as there could be some debris that has been sucked into the crack. That’s a good indication of a leak. Take a close look if the water stops at a wall fitting, pool light, or wall step, as there could also be a void in any of those areas. If you want to rule out the plumbing, you can shut off the pump, plug the drain, skimmer, and return lines with expansion plugs.

  •         Do you notice wet areas around the pool?

Taking a walk outside the pool deck and between the pool and equipment to see if there are wet areas will also help you detect a leak. If your pool has a downhill slope, you can walk down the hill to check if there’s water weeping from the hillside.

Remember, any part of your pool or equipment that shows signs of damage or wear is a suspect when it comes to detecting pool leaks. When there is a leak in your pool, chances are it will cause damage to the surrounding structures, and most of the time, these damages are visible.

Sinking pool decks or those that have cracks are already major symptoms of pool leaks. Holes in your liner that have been patched, rust forming around your skimmer, cracks in your pool floor, broken fittings—all these require your thorough scrutiny if you want to identify the case of your pool water loss.

At Nelson Pool Company, this is the first thing that our pool professionals look for when pool owners ask us to inspect their pools. Now, if you have discovered for yourself any sign of damage in your pool, or if there is an area in or around your pool which you suspect to be leaking, one of the first steps you can take is doing the dye test in these suspected areas.

There are numerous potential causes of pool leaks. Leaks in a pool’s plumbing system can develop for a number of different causes. For a more in-depth look at how our highly experienced pool inspectors use our cutting-edge technology to pinpoint the source of leaks, visit

The Swimming Pool Dye Test

If there is a location in your pool that you suspect is leaking, you can test that specific area with dye. Your goal in doing this test is to release a tiny amount of dye in the specific location where you suspect a leak.

When you conduct a pool dye test, make sure that your pool circulation system is turned off and that there is little or no wind causing movement in your pool water. Your pool water should be as still and as calm as possible when you do this test, so you are also required to be as still as possible as even putting your arm into the water can make the water move and the results of the test hard to assess.

To start the test, release a steady stream of dye into the area surrounding the suspected leak. Once you release the dye, it will tend to stay together and float gently with the subtle motion of the water moving. If there is a leak, you will see the dye being actively pulled out of the pool through the leak.

Dye testing is particularly useful around steps, skimmers, and lights. To detect a leak using this test, the key is to monitor the movement of the dye in the water. Take note, however, that cracks in your pool floor or in the main drain are not ideal for dye testing, unless you have scuba equipment that can allow you to get close enough to conduct the test in these areas.

Although leak detection using dye is usually not definitive, you can use this as a great and easy tool if you want to detect your pool’s leaks by yourself. If you’re ordering leak testing syringes, don’t order too many of them as you will only go through it very quickly when testing your pool.

As a word of caution, remember also that it is often difficult to find a leak using only dye. Even when you detect a leak using this test, you probably won’t be confident enough to say with certainty that you have found the culprit behind your significant pool water loss.

Dye testers are used only as supplemental tools in leak detection, so don’t expect the dye test to be a magic beacon pointing at your pool leak. Discover the ultimate pool leak detection specialist in Bradenton, FL.

Pool Leak Repair

If you have established that your pool is actually leaking, don’t fret. Luckily, there are several ways to make fixing a swimming pool a rather quick and painless process. Call us, Nelson Pool Company, so we can get your pool patched up and ready for swimming again.

Click here to view our completed pool construction projects.

Here are the specific steps you need to fix your concrete pool leaks, depending on their location.

  • Leaks in the underground plumbing

As a pool owner, it is your worst fear to discover that your pool leaks are coming from the underground plumbing—the large backhoe that comes in and rips up your pool deck. While pool leaks seldom emerge from this part of your pool, it does happen occasionally.

Whether the leak emerges from a pipe connector below the pool deck or under the skimmer, fixing leaks coming from the underground plumbing is not easy. Before you can fix the leaks, you need to determine if the leaks are coming from the pipes or not by shutting off the pump and plugging all the lines.

Through a pressure testing rig or stick, you can test the individual lines of your plumbing to check if they hold pressure. Pool professionals like us also introduce air into the pipe and listen for the sound of escaping air through a giant “stethoscope,” so you can mark the area where the repair should be done.

If the length of your pipe run is very short, or if you find that the entire pipe is already badly damaged, it is best to replace the entire pipe and just leave the old pipe in the ground. If your pool has a short pool deck apron, which is about 3 to 4 feet in width, you may choose to tunnel under the deck then cut it and dig. Usually, just a few hours of digging is enough to have the skimmer pipes totally unearthed. You may also want to dig up enough dirt under the deck to unearth the underside and use heavy timbers cut to size to hold up the pool deck.

Your other option is cutting the pool deck using a concrete saw, and then busting up the deck and digging out some dirt until the leaking pipe or cracked pipe fitting is finally exposed.

Once you have located the leak in your underground plumbing, the next step is to cut out the damaged part and replace it with new. Remember to make a solid plan first before you break out the hacksaw, since choosing the wrong option might only make things worse for you.

If all you need is a simple fitting replacement, just make sure to have enough room to connect the new fitting to the pipe with a coupling. If your plumbing needs more complicated repairs, however, you need to come up with a diagram to take note of all the fittings and equipment.

Either way, the most common way of fixing an underground plumbing leak is by replacing bad glue joints or cracked fittings by cutting out the old and gluing in the new PVC pipe and fittings. As you cut the new PVC pipe, make sure to add ½” to your measures.

To clean and soften the pipe, use a PVC primer on it for about 30 seconds before adding copious amounts of fresh PVC glue. Wipe up the drips of glue after pushing the pipe deep into the fitting and hold it for around 10 seconds.

If you are gluing 90’s and 45’s, there’s a way to get the angle correct when gluing them in place. Glue them in place with a length of PVC pipe inserted into the other side, so the fitting faces the exact direction it needs to face.

For threaded male PVC fittings, you need to smear a silicone sealant over the threads before wrapping the threads several times with Teflon tape. Then, tighten a threaded fitting in by your hand and give it another 1 to 1 ½ revolutions with large pliers.

Make sure that the final connection is tight, even if that means having to bend some pipes or pushing the equipment to make the final glue joint connection as tight as possible. Remember that pipes and pool equipment usually have an inch or two of play in them, so don’t hesitate to push and pull as needed when you make the final glue joint.

There’s a reason why pool leaks coming from the underground plumbing is the most dreaded of all. This is because in most cases, replacing a simple fitting requires replacing other fittings that are in the way of the new connection. You may also need to reinstall the chlorinator or other pool equipment plumbing.

  • Leaks in the tile

If your concrete pool has the traditional perimeter tile band at the waterline, then most likely, you will find the leak inside the skimmer. But in cases where the pool bond beam cracks behind the tile and the tile itself, you will notice your pool leaking water through a crack right on top of your pool wall.

Here are the three ways to repair pool leaks in the tile:

Ø  Using epoxy

Directly squeeze the bottle of epoxy onto the crack in the tile. This is effective even if the crack is underwater, as the epoxy does not wash away. If the leak is coming from the tile grout, you can simply squeeze the epoxy on top of the leaking grout before smoothing the epoxy onto the surface of the cracked tile. Let the epoxy set for at least 45 minutes before checking if the leak has been adequately sealed. 

Ø  Rubber-based sealant

Applying a rubber-based sealant to fix a tile leak is pretty much the same as applying an epoxy. The only difference, however, is that if the tile cracked widely, you will have to apply it directly with your hand several times to make sure the source of the leak has been adequately sealed. Curing time for a rubber-based sealant is also typically longer than that of the epoxy.

Ø  Putty

Squeeze a small amount of putty onto the crack or grout without touching the putty with your hands. After 20 minutes, check to see if it has successfully covered the leak.

  • Leaks in the skimmer

At some point, in-ground concrete pools will develop leaks at the skimmer. Over time, the contraction and expansion of the pool and deck will break the seal between the pool wall and the skimmer, causing leaks.

The most common way to fix a leaky pool skimmer is by applying repair putty. Once you have located the exact area of the leak along the seam, the first thing you need to do is to remove a piece of underwater pool repair putty from the tube and knead it with your fingers several times into the area of the leak.

Then, smooth out the putty using your fingers and wait for about 24 hours. By that time, the putty should have already changed into a white color, indicating that it has already cured and that you can finally turn the pump back on.

Skimmers can develop leaks that weaken the pool’s framework if not addressed promptly. Click here to find out if your pool leaks are originating from your skimmers, and correct them immediately to ensure the long-term health of your pool and wallet.

How deep are pool pipes buried?

Pool pipes in Manatee and Sarasota are buried 2.5 feet to 3.5 feet on average. This is to ensure that the pipes are protected from freezing, surface soil slip, debris, and other elements that may affect the plumbing system and drainage of the pool.

Having an inground pool is cool until you have to find leaks and fix them. That is why inground pools are built in such a way that leaks can be avoided at all costs. Professional pool builders ensure that the pipes are buried deep enough to protect them from leaks but not too deep just in case a need to check or fix the pipes may arise.

There is no guarantee that inground pools will stay in the most pristine condition over the course of time. Of course, you can take advantage of preventive measures and maintenance routines to lengthen your pool’s lifespan.

Those preventive measures include knowing how and where your pipes are buried so you know what you tell your pool experts just in case a leak detection might be needed.

Let’s have a quick overview of what the pipes under your pool look like.

From the pool, water circulates through 2 to 3 drains that lead to a filtration system. Water is continuously filtered out to remove small debris and other types of dirt. These drains are usually located on the bottom part of the pipe system.

Aside from this filtration system, water is also filtered out by skimmers. They are in charge of removing dirt that floats on the pool’s surface. They ‘skim’ through the surface level to catch leaves, oils, etc., hence the name.

Most of the pools we’ve worked with here at Nelson Pool Company have vacuum ports. These ports serve as vacuum cleaners, but instead of air, they suck water so they can clean the pool. 

All of these lead to the main pump, the heart of the pool system. It’s simply an electric motor that spins an impeller inside the pump housing. It drives the water from the various drains and filters mentioned above back out to the water inlets, keeping your pool safe and clean for you to use.

The pipe system being composed of multiple parts is part of the reason why pool pipes are buried deep.

How can I tell where my inground pool is leaking?

To tell where your inground pool is leaking, check for wet areas around your pool and try the pool dye test. You can also hire professionals like Nelson Pool Company for an expert assessment of your pool’s condition.

For steps in conducting the pool dye test, simply follow the steps above.

But before testing your pool for leaks, it’s important to ascertain if a leak is really the culprit. There are many ways a pool can lose so much water, and there are a lot of instances that it’s not caused by a leak. Evaporation and frequent pool usage should also be looked into.

To verify if it’s really a pool leak that causes water loss, you can try the bucket test mentioned above. It is one of the most simple yet effective ways to tell why your inground pool is leaking.

Why is my inground pool losing water?

An inground pool can lose water because of leaks. It can also be because of evaporation or water splashing out because of frequent usage.

Let’s discuss some of these reasons in detail:


Water evaporates because of heat. If your pool water has too much sun exposure, it will likely lose a significant amount of water. The bucket test is one good way to prove if your pool is simply evaporating because of heat. Water loss through evaporation can be avoided by covering your pool when not in use.

Splash Out

If you’ve got playful kids going in and out of your pool, there is a chance that your pool will lose a lot of water. Splash-outs are completely normal and shouldn’t be a cause of worry. Still, it’s important to regularly check how much water your pool loses. If water loss is more than ¾ inch, it might be time to check for leaks or ask for the help of a professional


If you have confirmed through a bucket test that water isn’t simply evaporating or splashing out, then it’s most likely a pool leak. To avoid further damage, it’s best to consult an expert immediately. It’s crucial to determine where the leak is as soon as possible and have it fixed.

It’s also great if you know how to look for the leaks yourself. Pool repairs consume a lesser amount of time if the pool owner already knows where the problem is. All that’s left to do for the pool repair team is to verify whether the leak is really coming from where you suspect it to be and fix it.

Need help with repairing pool leaks in your concrete pool? Call us, Nelson Pool Company, at 941-256-4079 today and we will help you throughout the entire repair process.  What’s the price of pool leak detection? Find out now – click here!

Work quality and customer satisfaction are our top goals. Learn more about us here.

In case you can not view this video here, please click the link below to view Your Complete Guide to Fixing a Pool Leak on my YouTube channel:

Get ready to experience the ultimate luxury and relaxation in your own backyard – contact Nelson Pool Company today to start creating your dream pool with their expert team and turn your outdoor space into a stunning oasis that will impress and delight for years to come!