I just noticed last night that the return nearest my pump was bubbling profusely. It was very apparent with the pool lights on.
I did a little trouble-shooting. I turned off that return and turned on another. The bubbles moved to that return.
The weird part to me is that I have NO air or bubbles in the pump basket.
I do have a SWG and it was running at the time.
I opened the bleeder valve at the top of my cartridge filter but I got pretty much straight water.
My pump was on low speed.
Anything to be concerned about? I don't THINK the pool is leaking...