New Member ..Question about CYA test

Hello, I have been reading many post on this. I am confused at how to do this test. When doing the test and pouring the solution into the test bottle with black dot...do you wait till you no longer see the black dot? Or do you stop when the black dot just starts to fade?
I was doing it when I no longer seen the dot but the pool store told me that you do it when it starts to fade then stop....it was odd because with there test they came out at 100-CYA and when they used my tester it came out 80-CYA
Any help would be appreciated. Thank you

You read it when you can no longer see the black dot.

Welcome to the Pool Forum!

There are videos here: http://pool9.net/tk-guide/

One tip: when testing CYA, you need outdoor -- but NOT direct -- light.

You can pour the solution back into the squeeze bottle and repeat the test over and over.

Just to be clear, I don't mean that you can re-use the solution the next time you want to do the CYA test, but you can repeat the test with the solution you have mixed a number of times in the current testing session. This allows you to "master" reading the test, because it is difficult to determine when the dot disappears.

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