Water Evaporation
A concern that some above ground pool owners have is when to determine if the pool has a slow leak. You may notice that the pool level slowly goes down, is it a leak or is just natural evaporation.
Adding Water Everyday?
If you're putting water in the pool every day, chances are you have a slow leak problem You should double check all patches to make sure that they are secure. It might be a good idea to double patch areas for a better seal.
There is some pool specialist that can check for the source of the leakage by using sophisticated sound and color dyes testing.
Natural Causes of Water Evaporation
There's no exact amount of water you may loose every day since there are four key factors that determine evaporation: exposure, water temperature, and humidity.
Exposure is how much sun and wind the pool gets everyday. Sun is great to warm up the pool, but those rays also burn off a tiny amount of water. Solar covers are a great way to prevent evaporation from exposure.
Water Temperature - As the pool heats up during the day, it cools off at night. That cooling off period is when some evaporation happens. Turn on the pool light on a nice summer night and you'll see the mist of water evaporating from the pool.Cause
Humidity - The more humid the environment, the less evaporation that will happen. Which means during a period of dry weather, you would expect to see a bit more evaporation.
In addition, constant use of the pool will cause loss of water.
The Bucket Test
The best way to test for evaporation is by using the bucket test.
Take a 5-gallon paint bucket from Lowes or Home Depot. Make a mark with a permanent marker at about the halfway point. Fill the bucket with pool water, so it's the same temperature and has the same chemicals, up to that point, and set the bucket right beside your swimming pool. Simultaneously, use a pencil to mark the water level on your pool skimmer basket. Mark your skimmer basket so that way you don't ruin the liner with a marker.
This test will help you determine how much water has evaporated from the bucket and from the pool. Make sure to turn off any pool heater during this test.