What to do about air in RO line

[tapdrinker]

I noticed last night that I had air in my RO lines. It was causing it to run sub par. What causes this and how do you fix it? I should mention there are no leaks and the feed pipe to the pump had no air in it. It started right after the pump.

[maple flats]

Sounds like you have a leak in the suction side of the high pressure pump. It might not even leak until that pump is running. Do you have a recirculation tube? If yes, suspect that first.

[wmick]

This sounds like it could be cavitation... (pump trying to move more liquid than the feed pipe will allow, easily.) Try increasing that line size, or lifting the feed tank up, to create some head pressure for the pump.
https://www.ansys.com/blog/what-causes-pump-cavitation
https://empoweringpumps.com/what-causes-cavitation-triangle-pump-components/