We have a 20x40 Guntie pool and we noticed over the winter our pool drained more than what we had at the end of the season. We live in Michigan and our pool company said that is common, however it did not happen the year before. We now have had water fully in the pool for 2-3 weeks and have lost about 4 inches total of the water we put in. We have no idea what could be causing this leak and want to try to fix it ourselves. Any suggestions on what it could be? The pool drained till about 3 feet of the deep end. My husband tried food coloring at the bottom of the pool and really didn’t have much luck but he couldn’t stay under for that long either.