I added a raised spa a year ago. Last week as it got really hot in here during the day I noticed that my spa loses 1.5 inch from 8:00pm -7:00am (pump off) vs. pool losing 0.250 inch. Temperatures go down to 60 at night. I did a bucket test on the pool and it is alright (0.250 inch overnight for bucket and pool) but the spa kind of worries me. I calculated the water lose in gallons and turns out both the spa and the pool are losing the same amount of water but how could a spa go down 1.5 inch.? I assume if I do a bucket test on the spa the bucket wont evaporate 1.5 inch vs. spa. My spa spillovers to the pool. My concern is if I have a leak or not. No visual leakage anywhere.