Air leak pressure test help

I need help finding an air leak in my pool system. I tried doing a pressure test but I cannot plug both ends of the line. I have one line from the pump to the skimmer and it t’s off to go to the main drain underground. I can plug the hole in the skimmer but i cant plug the main drain at the bottom of the pool because my water has a lot of algae.

When i start my pump I dont get any air bubbles until about 30 seconds. Im thinking there is either a leak from the pump to skimmer, or leak from main drain to where it connects to the other pipe. Unless debris in the main drain is causing the air bubbles.

what can I do to test the line? Would i have to find the t connection underground where the skimmer to pump line and main drain line meet, disconnect the main drain line, plug it, then pressure test the skimmer to pump line. Or just get someone with a scuba suit to dive down into my green water and plug the main drain.

When I start seeing the air bubbles in my pump basket there is a knocking sound in my pipe that comes out of the ground with a 45 elbow and into my pool house.

Hello N33l10,

There is no easy answer to this question. The only true way to test a line would be a pressure test. Since the pool is not a happy color, this may prove difficult for the average homeowner. There are a number of leak detection companies that can assist you with the testing and repair. In this situtation, I would defer to the specialist in that area. We also have a product available called Marlig Fix A Leak. This patented formula is made of a concentrated material designed to seal leaks in pools and spas.  Fix-A-Leak can provide a permanent seal for holes up to 1/8 inch diameter in the walls, floor, shell, and suction and plumbing lines. Depending on the size of the hole in your plumbing, Fix A Leak could be a viable option.

Thank you,

Alan