My inground gunite pool has a water leak of about 2" per day. When the water level was just below the skimmer mouth I turned the pump off and the water level stayed there for over 7 days so I thought the leak was at the skimmer mouth. I decided to turn the pump on today and balance the chemicals, turned the valve to only suction from the wall vacuum and the bottom drains, and the water level started lowering like before. Now the water level is about 2" below the skimmer mouth, so now assume the leak is in the plumbing somewhere. Now is my only option to hire a leak detection company to pinpoint the actual leak?