If you suspect that you are losing water from your pool then the first thing to find out is how much water you are losing and from where.
Depending on wind speed and temperature conditions, you can lose up to 1/4" per day though evaporation. Also check all the equipment and the backwash or drain line to make sure they are not leaking.
Here is a simple test to determine whether you are losing water and to give you some clues as to where the leak may be.
Fill a 5 gallon plastic pail about 2/3 with pool water. Put it on the second step from the bottom of the staircase with some rocks in the pail to keep it in place. Because the pail is partly immersed in the pool water it will stay at the same temperature as the pool and lose water to the air at the same rate. Since we know the pail is not leaking, we can use it as a control if we expose it to the same conditions.
Mark the water level in the pail and on the skimmer faceplate with a pencil. Run the pool with the PUMP ON for 24 hours and mark the pail and the skimmer again. Turn the PUMP OFF for 24 hours and mark the pail and the skimmer a third time. Using a ruler or a tape measure, measure the difference between the first two marks on the pail and the skimmer. Then measure the difference between the second and third mark on the pail and the skimmer. Write down the results.
If the pool and the pail both lost the same amount of water, you probably do not have a leak. You can repeat the tests again at another time, if you are still not sure.
If you lose more water with the pump on, the leak is likely to be in the return water lines, as these are under pressure when the pump is on.
If you lose more when the pump is off then likely the water loss is from the suction lines. These are under suction when the pump is on and will suck air into the system rather than leak water until the pump is turned off.
If the water loss is the same with the pump on or off, then the leak is most likely from the shell of the pool. This could be a hole in the liner, bad gaskets or cracks in the skimmer, main drain, staircase or lights.
These tests are only an indicator of where the water leak may be. Sometimes the results are deceptive. Suppose, for example, that the leak is through a small hole in the liner. As the water passes through the hole, debris, such as a leaf, can easily plug it up throwing off your measurements.
It is very important that you take accurate measurements. Do not guess. Do not use the pool during these tests. Redo the test if there was heavy rain during the test period.
We hope this information will help you to decide whether you are losing water and, if you are, where you may be losing it from.
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38 Luscombe Dr., Simcoe ON - 519-426-3920