Leak?

[randypape]

Hello I'm losing about 1 1/4 inch of water in a 24 hour period With the pump running. I lose about a half inch of water in a 24 hour period With the pump off. I notice if I have my valve in the middle with the skimmer and main drain both open I'll get a lot of air bubbles in the pump basket. If I close the main drain on the valve then all the air bubbles call away . I dye tested pretty much everything inside the pool the best that I know how but not the main drain because I couldn't get down there so I'm wondering what suggestions might be for for next step . Do the air bubbles indicate a leak in the main drain pipe? I appreciate any help with this matter thank you Randy

[Denniswiseman]

Air in the pump basket is indicative of a suction side air leak however your experience when shutting off the main drain stopping the bubbles doesn't coincide with losing more when the pump is running against the pump off as air coming in wouldn't leak when running
Do you have a hydrostatic relief valve in your main drain as this could be faulty. Losing water and sucking in air with the pump running

[randypape]

I'm not sure if it has one of those valves because I have a vinyl liner in this pool. I used to get air and had a the plumbing leak which I fixed . This is a different problem and like I said when I close the main drain the bubbles go away but I still get the water loss So looks like I'll have to get the main drain check thanks