Air coming from return

[swimnut]

i have a constant flow of air bubbles from one of my return lines. The other one does not show any bubbles. This continued thru-out the season last year. I do NOT loose and water whether the pump is running or not. This year I noticed the bubbles are worse when the rooftop solar panels are activated. Also, something new, on occasion the return water from the outlet with the bubbles has had a dark appearance and plastic like material floated to the surface.

[ryanarguello]

I think there is some technical fault which can be recognized by a professional pool repairer. There might be problem with pool pump.
ventis ventilation systems

[Denniswiseman]

Hi

Air coming out of the returns is a sign of air being drawn in from the suction side of the pump
Check your suction side joints and especially the pump basket "O" ring, lubricate it with silicone grease or vaseline. This will allow it to tighten down more securely and seal minor imperfections.

The only place plastic material could enter your system is from within. Something might be breaking down, the most obvious would be the impeller of the pump which is rotating and could be rubbing against something.

An internal inspection of you pump may show something more obvious

[free]

check the intake pipe going to your pump they may not leak but can suck air I have had to cut and redo some & others replace o-ring.