I have a 10k in ground pool with a vinyl liner. At the end of the summer, I started losing water....ALOT of water. I continued filling it with water for about a month. Once closing time rolled around, I figured I would let it drain until it stopped so I could find the problem. Well, it hasn't stopped. I've still got knee deep water in the deep end and losing water each day about 1.5-2 inches each day lost.
The liner is starting to sag and has me worried. I finally called a professional who said he was unable to make it out for a few weeks, but thought it could be the drain. I always thought my drain was for appearance as there appears to be no plumbingto it. I unscrewed the cover and pulled off the drain and found nothing. There is no hole and nothing to be plugged. I have walked all around the pool and found no holes or tears in the liner. I am at a complete loss as to what can be causing this issue.