When I'm SLAM'ing My Pool, Can I Use "Chem Out" On a Water Sample to Get An Accurate pH Test Result?

chuckles98103

Gold Supporter
Sep 1, 2019
9
Seattle, WA
The title says most of what i'm asking .. a little more detail:

in the middle of a SLAM, can i pour off say, 50ml of pool water into a container, add a couple of granules of "chem out" (which removes the chlorine) ... then, do a quick chlorine test to ensure i've removed it .. and then do a pH test on the sample to get an accurate pH reading?

i'd like an accurate pH in the middle of a SLAM - so if i can't do it this way, is there another way?

thanks for any thoughts.
 

beautifulpool

Well-known member
Jun 2, 2019
101
North TX
The title says most of what i'm asking .. a little more detail:

in the middle of a SLAM, can i pour off say, 50ml of pool water into a container, add a couple of granules of "chem out" (which removes the chlorine) ... then, do a quick chlorine test to ensure i've removed it .. and then do a pH test on the sample to get an accurate pH reading?

i'd like an accurate pH in the middle of a SLAM - so if i can't do it this way, is there another way?

thanks for any thoughts.
Ive used an additional 1 to 3 drops of R007(Thiosulfate) to neutralize excess chlorine residual - Depending on my how high my slam level was.
 

chuckles98103

Gold Supporter
Sep 1, 2019
9
Seattle, WA
Here's the thing about wanting to track this: my other numbers are all quite reasonable:

C.H.:200, T.A:130, CYA:30, Temp:90 degrees, FC:~14ppm

... and during the SLAM, my pool was using maybe 5-6 ppm FC per day to as whatever algae was in the pool consumed it, which i replaced with liquid Clorox each day.

I looked at the Taylor Test Kit "Saturation Index" tool .. and if my pH is high (which it appears to be at ~7.8), my saturation index is around ~0.4, which is on the high end .. but it's perfect (~0.2) if my pH is closer to 7.6/7.7 ... so that's sort of why I'm interested in testing pH.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,396
Laughlin, NV
If you quickly do the color match after adding the pH indicator, the reading will be very close to correct. Especially as close to 10 ppm FC as you are.
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
32,720
Sebring, Florida
If you are doing it to track CSI, I doubt CSI will have ANY affect on your pool. CSI is only important in pools that cannot maintain their pool water within our normal guidelines...........and you should have no problems. What is the CH, TA, and pH of your refill water?

On top of that, even if your CSI is not what you want, it is completely irrelevant during a transient condition like a SLAM.