Pool leaking and losing water? Find leak and sanitize!

Leaking pools are a real nightmare for many owners. Initially, the water loss is harmless, but over time, in the absence of remediation, can cause enormous damage. Water loss is not only a problem from an ecological point of view. The leaks can break the entire pool system, and in the worst case scenario, it may require a general renovation.


Our pool naturally loses some water through evaporation, some through splashing out, and some through backwashing sewage. Also, obtain water from rainfall. My rule of thumb is that if you routinely add more than 5cm of water to your pool per week, you probably have a leak worth spending some time and possibly money to fix.

Pools are supposed to be watertight, but the sealing materials will deteriorate as other parts of your pool shift and settle or simply wear out. Pools can leak through any fixtures or accessories, piping, or even directly through the shell.

Here are the most common causes at a glance.


Osmosis in pools
is one of the most common causes of damage and the main reason why pools leak and remediate.


The high chemical but also physical stress can cause cracks through which water escapes.

Find leak

Finding a leak is often not so easy. Here are quick tips to elicit the leak as soon as possible.

Step 1

Check the obvious first. Here is a list of common problems that could indicate a leak, in no particular order

  • Are there any leaks from the equipment support?

Take a close look at the filter, pump, heater, and plumbing valves.

  • Are there wet areas around the pool?

Check the floor for moisture. Walk around the pool and past the pool and equipment. Check for wet soil and sunken or eroding areas.

  • Do you have a pool with vinyl liner?

Look for cracks or separations around all fittings, skimmers, returns, cleaning line, lights, steps and corners.

Step 2

If you want to confirm a leak, try one of these techniques to check it out. If you suspect your pool is leaking, there are several ways to check.

  • Mark the water level of the pool on the skimmer. Use a piece of tape or a grease pencil to mark the water level. Check the mark 24 hours later. Your pool should not lose more than 1⁄4 inch (0.6 cm) per day. Otherwise, a leak is indicated.
  • Place a bucket filled with pool water on a pool step (weigh it down with a stone or brick). Mark the water level on both the inside and outside of the bucket. Make sure that the water levels inside the bucket match the water level of the pool water outside the bucket. Mark the mark 24 hours later. If the line on the outside of the bucket drops more, a leak in the basin is indicated. This test must be performed with the pump switched on and then again with the pump switched off.

Step 3

Determine the location of the leak. If you notice your pool losing water, turn off the filtration system and note where the water stops dripping. Vinyl liner pools must contain water at all times! Finish this test if you have a liner pool and the water level is dropping quickly. Start adding water and call a pool professional.

If the water stops at the bottom of the skimmer opening, the leak is probably in the skimmer or filter system (including the pipes). If you suspect you have a leak in the filtration system:First, check to see if you see air bubbles in the water in the return line when the pool pump is running. If this is the case, there is a leak on the suction side of the filter system.

Make sure that the pump basket cover is tight and that the cover O-ring is lubricated and in good condition.
If the water stops at the fixture, the leak is probably at the fixture housing.
If the water falls under the fixture, there may be a leak in the drain at the bottom of the basin.
If the pool loses more water when the pump is running, the leak is on the return side of the system. In this case, check the drain or backwash line for running water,

If you suspect you have a leak in the skimmer, fixture or liner, look closely for what looks like a crack, gap or tear.

Step 4

Place a drop or two of the dye test solution or some of your pH indicator test reagent near a suspected leak. Do this with the pump turned off and the water at a standstill. Check whether the dye is sucked into the crack, crevice or fissure.

Redevelopment – What to do?

It is important to repair leaks not only to save water, heat and chemicals, but also to prevent undermining structural components of the pool and washing away the fill dirt that supports the pool walls and deck.If the pool is leaking there are two options. You do it yourself and usually invest a lot of time and risk no fix and a potential worsening of the problem. Or you can have it repaired by a certified specialist company. In any case, however, you should ask a specialist for advice for the appraisal and assessment at the beginning away.


Repair leaks that you have identified. Your treatment of the leak depends on its location and type:
Skimmer Leaks: The most common leak is a disconnect between the plastic skimmer and the concrete pool. This can be easily repaired with pelvic putty.
Light leaks: It often happens that the line pipe comes loose, breaks or separates from the niche. This is difficult to repair. There are several methods to repair a bad line connection. A two-part epoxy that dries hard with putty, silicone or sealant are ways to fix this problem.
Liner leaks: simply patch them with a vinyl liner patch kit. If you are underwater, use a wet patch kit.

New coating system

There are numerous systems on the market when it comes to pool waterproofing. In the meantime, we rely exclusively on and recommend the 2-component liquid plastic
. The material is unbeatable in terms of resilience & durability. In the initial purchase it is usually a little more expensive but in the long run you save a lot of time and money by missing new renovations and resealing.

It is therefore the much more sustainable solution from an environmental and financial point of view. Moreover, all RAL tones are possible and the system can be applied to any pool system.

Note: We offer refurbishment solutions for steel, aluminum, sheet metal and polyethylene pools only.


Submit project request

Initial technical consultations and information as well as quotations are free of charge. We request that all necessary information be provided to allow for accurate bidding.

25 years of innovation in the waterproofing and coating sector with polyurea.

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