Ph dropping when shocking

[fklarrison]

I'am shocking my pool to clear up cloudiness and I notice when I shock that my ph drops to about 7. I thought that it was suppose to rise when you have high chlorine levels

 

[faby3003]

What type of chlorine are you using while shocking your pool? Can you post a full set of test results?

 

[fklarrison]

Liquid 10% chlorine.
Fc=23
Cc=0
Cya=90
Ph=7.0-7.2
Ta=110
Ch=230
Salt=3100

 

[shortdogOH]

They say that pH reads higher than it is at high FC levels. I think that is more because the test is skewed, than the pH actually rising in the water, but I could be wrong. In any case, I never noticed a rise in pH when I was shocking, more like a decrease if anything, similar to what you are suggesting.

Your TA and CYA are a little higher than recommended (TA moreso). which might lead to a natural lowering trend in pH, but again I am guessing.

I would monitor it, and if it drops further, take action to adjust it back to 7.2. Check again at normal FC levels (once shocking process is complete), and adjust again as necessary (back to normal 7.5-7.8 level for swimming)

 

[JamesW]

pH won't be accurate when the FC is over 10 ppm. What was the pH before adding the liquid chlorine?

 

[lorinmoss]

It is possible that your chlorine in bleaching out your pH indicator. Does your test kit have you adding chlorine neutralizer? Is your chlorine level above 10 ppm?

 

[ROB N]

pH won't be accurate when the FC is over 10 ppm. What was the pH before adding the liquid chlorine?

x2

 

[fklarrison]

I'am using the TF-100 test kit. My ph was 7.5-7.8 before shocking.

 

[JamesW]

pH won't drop when adding liquid chlorine, it will rise a little bit. Don't rely on pH testing when the FC is over 10 ppm.