Cannot get good color match on the pH tester that comes in TFtest kit

[CFlaPool]

I can never get a good color tone match on the plastic kit. I do get good matches on our 25year old Guardex test kit using porpoise test bottles from pinchapenny. Does anyone else have this problem, or is it just me? Also, is there a recommended best tool to measure pH?

 

[Texas Splash]

The pH test frustrates me as well. Best things I do for that pH viewer is ensure I have a light background behind the viewer. I also like to do the test outdoors with natural light around me. That, coupled with some beige home siding helps. Lastly, when it's 7.5 or lower you should really tell. It will be orange or lighter. It's those 7.7-7.8 and above, the darker lavender shades, that are tough to call. But if it's that dark, you probably need some muriatic acid.

 

[ajw22]

A similar report was made here...

Newb OB with BYOP in Buckeye AZ - tuning the SWG

End CYA at 70, but like you're adding salt, shoot for low and creep your way up to it, giving a few days between dosing. If you're due for a filter cleaning, do that first. You don't want to clean the filter for a few weeks after adding solid CYA to the skimmer in a sock. (DON'T USE LIQUID CYA!)...

www.troublefreepool.com

@Sarah and Nate may want to make note of this.

 

[pjt]

Two additional techniques:

1. Try holding the block sideways or upside down. Sometimes that helps distinguish colors better. I also use two old hotel keycards to mask off areas and narrow down my decision.

2. To get a consistent backlight, hold the block in front of your computer monitor with a blank white screen displayed (I use Google's homepage).

 

[CFlaPool]

A similar report was made here...

Newb OB with BYOP in Buckeye AZ - tuning the SWG

End CYA at 70, but like you're adding salt, shoot for low and creep your way up to it, giving a few days between dosing. If you're due for a filter cleaning, do that first. You don't want to clean the filter for a few weeks after adding solid CYA to the skimmer in a sock. (DON'T USE LIQUID CYA!)...

www.troublefreepool.com

@Sarah and Nate may want to make note of this.

I agree with that other (marathon) thread that the TF color blocks look faded. It looked the same as mine when I have a pH of 7.8.

 

[proavia]

As a test, try using 4 drops of the pH reagent instead of 5.

I have the older comparator block (always stored inside in a dark cabinet) and I have an easier time discerning the pH reading when using 4 drops. Holding the comparator against a white background helps as well.