I haven't been able to detect any leaks, but I filled the pool up to normal, just below the top of the skimmer and within 2 days it had dropped almost 2 inches. I don't see any standing water around the pool and can't determine what the heck is happening. It's an AG 18X33 ft oval pool with a liner. The pump is brand new and there are no leaks around the filer. Is there anyway to test for a leak in the liner? ANY advice would be greatly appreciated.

THANKS!!!