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sturev
06-24-2010, 10:00 AM
Hi All,

When I test my CYA and follow the instructions (Taylor K-2006), I don't get a CYA reading. BUT, I read somewhere on here (I think) about letting the bottle sit for a few minutes after you're done shaking it (like 3 min's), and then test. If I do this, I get a reading of 30... Is this accurate? I haven't tested to see what happens if I let it sit longer (wondering if it would show even more). I'm not having any issues with my water; just wondering about this one test.

Happy swimming! :cool:

aylad
06-24-2010, 11:21 AM
In my experience, it doesn't matter whether you let it sit for 3 minutes or 5, or 8--the reading is going to be almost the same. CYA is such a subjective test and so many things can interfere with it--lighting, temperature, etc that your best bet is just to make sure that you are as consistent as you can be when you test, so that your results are as consistently true as they can be.

When I plan to test for CYA, I use water at room temp, I mix my water and reagent, shake for 30 seconds, and set it on the counter while I run all the other tests I'm gonna run. After that, I do the CYA test, in the same place in the kitchen, with the same lighting and blinds open, and facing the same way. Sounds silly, I know, but I have flourescent lighting above me and a picture window behind--if I test facing the window, or with the blinds closed instead of open, or with the overhead light off, it skews the result. As long as I test with the conditions as consistent as possible, then I know to trust any changes that my testing shows me.

Janet

waterbear
06-24-2010, 11:27 AM
If you let it sit TOO long you might find the reading actually goes down very slightly. I do what Janet does...mix the sample first, shake for 30 seconds, let it sit while I do my other tests, and then reshake and read.
Doing the test the same way each time and in the same lighting is the key to getting consistent results. I read my CYA tests outside in open shade with the view tube held at waist level.

AnnaK
06-24-2010, 07:11 PM
I'm the one who suggested letting it sit for 3 minutes and shake it again just before reading. Guess what? That's just about the time it takes to run the other tests and record the results and treatment plan, if any :)

Poconos
06-24-2010, 07:30 PM
Jan,
I think you forgot to mention you stand on one leg and put a sheet of aluminum foil on your head.:D
I couldn't resist.
Al

waterbear
06-24-2010, 08:04 PM
i'm the one who suggested letting it sit for 3 minutes and shake it again just before reading. Guess what? That's just about the time it takes to run the other tests and record the results and treatment plan, if any :)

exactly!;)

aylad
06-24-2010, 08:50 PM
Al,

:p :p :p :p ;)

Janet

waterbear
06-24-2010, 09:42 PM
I thought CarlD had the monopoly on tin foil hats.:cool: