Chart For Pool Chemistry Ideal Ranges?

[JasonLion]

You use aeration as one of a sequence of steps to lower alkalinity. Aeration raises PH without changing alkalinity. Acid lowers both PH and alkalinity. The two used together properly will lower alkalinity while leaving PH the same.

Rain is generally a very weak acid, a lot of rain water will lower PH slightly. Meanwhile the aeration from the rain hitting the surface will raise PH. How quickly the PH goes up depends on where you PH and alkalinity start out. The net effect could go either direction.

 

[NWMNMom]

OK, thanks. This makes me believe that the rain probably is the reason for the issues. I put some acid in to lower both ALK and PH - we like to keep ours around 7.2 and never over 7.4 for crystal clear water.

 

[Guest]

Rainwater is usually acidic and will tend to lower both TA and pH.