I have a polaris 380 (with booster pump) and have determined the line is leaking somewhere between the pump outlet and the pool inlet. I was loosing as much as 1" of water in a 20x40 pool (about 500 gallons) in a day when the polaris was running most of the time. When the polaris is not running and the pool pump is on most of the time I was loosing about 1/2". I put a plug in the polaris line and turned the valve off from the booster pump discharge and have lost no water in two days.

So, how do you fix this. Do I have to cut into the concrete decking around the pool, or do I just dig a big hole five feet out (the concrete is 5' wide) and then dig under the concrete to start running a new line. Is there a better fix?