PH testing using palintest pool tester

[amin36]

Guys

For PH measurement I am using palintest pool tester.i attach the picture of the tester below
I live in iran and I don't have access to taylor test kits
Readimg PH - Further Reading from TFP i came to this below:

" The Taylor R-0004 pH Indicator solution has a proprietary combination of chlorine neutralizers already in it that try and keep the pH the same when chlorine gets neutralized, but there's only enough to neutralize roughly 10 ppm FC or so of chlorine. "

Does anybody know whether palintest phenol red tablets for measuring PH contain ANY chlorine neutralizers in them in order to have an accurate PH measurement especially when we are dealing with free chlorine level between 4-6 ppm with 30 ppm CYA in the water?

Does this FC amount effect the accuracy of the PH test?

I treid to contact palintest but it is hard to receive an answer from them

 

[ajw22]

@JoyfulNoise you know anything about the Palintest FC test?

 

[JoyfulNoise]

From the manufacturer's technical documents -

Phenol red tablets contain a dechlorinating agent so that the test can be carried out in water containing normal levels of chlorine or other disinfectant residuals.

Most phenol red reagents utilize some dechlorinating agents because phenol red by itself is so sensitive to chlorine that it will not work without them. Test kits that use phenol red with no built-in dechlorinating compounds typically supply sodium thiosulfate drops to add to the test vial to neutralize chlorine.

In some ways it depends on their definition of "normal levels of chlorine" ... most public health and industrial authorities will say that 1-4ppm FC is considered normal and so their pH test is probably similar to Taylor's in that it will work all the way up to 10ppm FC but, beyond that, you will run into trouble. So you have to try to use it and see what happens.

The sign of chlorine interference with phenol red is pretty obvious. Chlorphenol red, the by-product of chlorine reacting with phenol red, is purple at a pH above 6.0 because it is a strong acid indicator. So you will know it's not working right as you will get unusually high pH readings.

 

[amin36]

@ajw22
Thank you so much

@JoyfulNoise
Thanks a lot.it was a perfect explain.i am so grateful...