Where does those small air bubbles come from?

[mazhiqiang69]

Hello
I just completed a SLAM, the water is back to clean now. When I brush the pool everyday, I find there are many small air bubbles on the vinyl under water (not foaming actually, but like the air bubbles when you put Coke in the glass, but they are much smaller). Where do they come from? Anything I should worry about?

Last test result:
FC: 39 (just stopped adding more 10% liquid sodium hypochlorine)
CC: ~0
PH: N/A (but before SLAM, it was 7.4)
TA: 70
Cal Hardness: 100
CYA: 100

Thanks!

 

[YippeeSkippy]

Are these bubbles near your returns? Do you have a SWG?

 

[mazhiqiang69]

I don't have a SWG, and these bubbles are not near my returns either, but just spread out on the interior wall randomly.

 

[Divin Dave]

As the chlorine killed the algae during your slam, there was a lot of outgassing from the algae being oxidized This is the most probable cause of the bubbles. Its nothing to worry about.

Once you get your pool properly balanced when the slam is done, particularly the FC and pH, and you brush the pool walls, the bubbles will subside.

hope this helps,

 

[mazhiqiang69]

Thanks, Divin. It does look like what you said, now, about 1 week after slam, everything is fine and the air bubbles gone.