You can feel free to post anything esoteric or detailed you like in The China Shop, but you might still get opinions about it.

On intense sunny days there is more chlorine usage and the chlorine level probably drops a little (the SWG may make up for this when the sun isn't as intense). Chlorine usage is acidic. When the chlorine level rises back up, the pH should go back up. So you can see if your chlorine level varies with pH and you can use my spreadsheet to see if the amount is what you would expect. If not, then I don't know what it is -- it's certainly not anything large enough to worry about since it goes both down and back up.

Richard