Why is there no more definitive CYA test?


Aug 9, 2016
lancaster PA.
I am curious why there is not a more definitive test for CYA, is one being worked on or is it cost prohibitive. I do the best I can with it but I had 2 other people do the test and we got 3 different interpretations. Of course I will use my number as I will be doing all the balancing. I use the Taylor test and I have also used the standard solution.. Thank you


Mod Squad
LifeTime Supporter
Jul 10, 2012
Tallahassee, FL
This test is a gurrrrrr test for me too! The one thing I have found to make it doable for me is GLANCE! Glance at the dot. Don't go looking for it or you will find it :roll: Pour the mixture to the first line (100) GLANCE in. If you see the dot pour to the next line, GLANCE in, keep going until you don't see the dot at a GLANCE.

I hope this helps. I have seen where several people like @jmikeb like the blue devil CYA test. I have not tried it so cannot tell you if it is any better to me.



Bronze Supporter
I have the Pentair version of the Blue Devil test. I really like. You pour your test water in to line A, then pour in reagent to line B. Mix with the plunger, wait 2 min, then move the plunger up until you see the black dot. Then you read ppm CYA off the plunger. For me it's easy as pie!


Well-known member
Aug 14, 2017
Vancouver, BC
The cya test is pretty easy, all you have to do is stop when you can't see the dot anymore. When in doubt use the higher value. Precision is low but good enough for pools.

But it isn't foolproof. It's incredibly hard to make something foolproof because fools are so ingenious. Lol


Well-known member
Jan 7, 2019
Spring, Tx
Is the reagent solution that comes with the blue devil the same Reagent as What is sold on TFP?

I ran out of blue devil reagent and started using my TFP reagent.

Using the same solution, I get two different results between the Taylor test and the blue devil test.

With blue devil I’m around 70. With Taylor I’m around 90.