PH Question

[dschribs]

If one is following the BBB method and not adding anything but bleach for chlorine - shouldn't the ph of the water stay relatively the same the entire summer?

What factors could cause a increase or decrease in ph?

Thanks!

 

[JasonLion]

Lots of things change PH, rain, aeration, chemicals, swimmers, leaves, pollen, and so on. Generally one or two of these factors ends up being much more significant than the others. The most common large effect factor in BBB pools is PH increases caused by CO2 outgassing. Swimming pools are carbonated, just as soda is. Because there is so much less surface area compared to the volume, the CO2 doesn't come out of solution nearly as easily. But some of it comes out and that process raises the PH.