SWG and Bubbles from return??

When my SWG is operating (Autopilot) I notice "Tiny Bubbles" from my return. It's hard to see in the day but at night I can see them across the light of the pool, and they are ONLY there when the SWG is active.

Is this the hydrogen gas produced by the SWG. I have read here that the SWG will produce chlorine and hydrogen gas. I can't find any leaks that would be pulling in air and again, it only happens when the SWG is on.

Thanks,

Russell

Russell,

Yes, these are hydrogen gas bubbles. They are not chlorine gas since this gets dissolved almost immediately into the water to become chlorine in water (hypochlorous acid). This is nothing to worry about, except these bubbles do provide an excellent source of aeration which is why the pH tends to rise in pools with an SWG. Keeping the TA low (about 80 if the CYA is 60-80) and the pH target higher (about 7.7) will reduce the tendency of the pH to rise and significantly reduce the amount of acid needed to keep the pH down.

Richard