Pools do lose 1″ to 1-1/2″ per week during summer months just by normal evaporation. When the days are warm and the nights cool evaporation is at it’s highest. Using the ordinary 5 gallon plastic bucket you can perform this simple test to determine if your pool is leaking.
Bring pool water to normal level. Fill bucket with pool water to about 1 inch from top. Place bucket on 1st or 2nd step of pool. Mark water level on inside of bucket. Shut off pump and mark pool water level on outside of bucket. Resume normal pump operation. After 24 hours, compare the 2 water levels. If the pool water (outside mark) goes down more than inside water level, there is probably a leak.