Is there a more accurate CYA test than Taylor’s?

vaindioux

Well-known member
May 15, 2015
74
Atlanta-GA-
I don’t find the Taylors CYA test very accurate.
Add testing water until the black dot about disappears.
I do that but never sure to what level it has to disappear. So I add like 3 drops and the results go quickly from 70 to 60 for example. The glare outside does not help either.
I m pleased with all the other tests in that kit.

Thxs

Pat
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
22,397
Laughlin, NV
Some members like a Blue Devil or Pentair (same thing) kit. It has a sliding dot.
When you do the CYA test, try this next time.

Once you have your solution ready, back to the sun, etc. Fill the vial to a line, say 80, lower the vial to your waist level and glance for the dot, you see it, add solution to the 70 line, glance, see it, repeat until you no longer see it with a glance. Then use the CYA value one step above the line you read. So if you stopped at 50, use 60 ppm CYA.

The vial is in logarithmic scale. So it is not viable to interpolate between the lines. Just use the whole numbers, such as 50, 40, 30, ....
 

splashpad

Bronze Supporter
Aug 2, 2017
1,994
SE Kansas!
I don’t find the Taylors CYA test very accurate.
Add testing water until the black dot about disappears.
I do that but never sure to what level it has to disappear. So I add like 3 drops and the results go quickly from 70 to 60 for example. The glare outside does not help either.
I m pleased with all the other tests in that kit.
Thxs
Pat
  • With CYA testing, good, bright, indirect lighting is crucial::
    • Too much and CYA will read higher than it is
      • (you will use less solution to 'obscure' the dot)
    • To dark and it will read lower than it is
      • (you will use more solution to 'obscure' the dot)
I would suggest getting the CYA/50 testing "standard", to teach you the best place to test your CYA. Since you know it should read CYA/50, find out where you need to be to get that reading.

It doesn't "go bad" so you can redo it as often as you like!
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
14,210
Bedford, TX
Pat,

I am not sure the Blue Devil sliding dot tester is any more accurate, but it is easier to use and more repeatable for me. I believe that repeatability is more important as you are really just testing to see where it was since the last time you tested..

The downside is that it use a lot more reagent...

Thanks,

Jim R.