Can someone please help me find the source of my pool leak? I have found and patched a couple of leaks in the pool before by dripping the pH tester, but this leak has eluded me thus far. The mystery part is that it doesn't leak if the Hayward Navigator is hooked up. But as soon as I disconnect the Navigator and let the water flow through the skimmer like normal then the water level drops by an inch or two per day. The Navigator hose connects to the bottom/back of the skimmer. There is also a main drain that is gravity fed into the skimmer, but it doesn't have any suction. No visible leaks around the pump.
Where should I look for leaks? Do these clues help to narrow it down? Any other tests to perform? Any help is appreciated. Thanks.