scum
I once had a problem with air in my
soap site gauge. I replaced all my lines thinking leak under vacuum. But the air persisted. I then noticed air swirling in my clear strainer bowl .The specific gravity of this
soap was heavier than what I was using before. My float on the hydro minder was at the end of the adjustment, so I added weight to the tank float. This added some reserve water-
soap level above the tank out let. My tank is very small, then it fills I get a lot of air in the tank from the hydro minder . I still had air in my site gauge that measures ounces per minute of
soap being injected and the clear strainer. I then tried changing the hydro minder tip to lower the
soap concentration going through the screen, this reduced the air some. I then bought a new strainer with the larger screen opening size. This fixed the air problem completely. Air is a Oxidizer, the air caused a
soap film on the screen, thus adding to the restriction of the filter causing more air and a perpetual cycle. A direct benefit was my pump quieted down. Good luck, Pete.