I had an in-ground pool built three years ago and am losing about an inch of water a day. I recently shut off the skimmer valve so all water would come from main drain. I checked today and the skimmer box is dry. I can see a little water at the at the bottom of the skimmer pipe and it is making a noise like a loud drip. Would this scenario confirm a leak in the skimmer line? Thank you in advance.