While evaporation rate for your area can be estimated using our Evaporation Index tool, you can eliminate evaporation all together by running a Leakalyzer test with the cover closed. This can be especially helpful in times when evaporation rates are really high in order to avoid confusing readings. If the cover rests on the pool water in any areas it will need to be completely dry, since the water evaporating off of the top of the cover could skew results.
