CYA test question

[dozer11]

When performing the test should the testing tube be in the light or in the shade? I stand with my back to the sun and get a different reading depending on if my body is shading the sun or if the sun is shining on the tube.

~50 in the shade
~30 in the sun

 

[mknauss]

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, ....

Also -

CYA - Cyanuric Acid Test

Cyanuric Acid (CYA) is the chemical name for what is commonly referred to as Stabilizer … Read more…

www.troublefreepool.com

 

[dozer11]

Okay I’ll try that. Thanks!

 

[IceShadow]

In the shade but brightly lit area (indirect light). Direct light will cut through the turbidity of the suspended particles and make the dot more visible, making it read lower than intended.

If you really want to be sure you've got the test dialed in you could get the 50ppm standard solution and test that. Sounds like your water should look pretty similar.

 

[dozer11]

My husband and I pretty much agreed 30-40 so rounded up and are going with 40 so I think we got it. Thanks!

 

[Toxophilite]

Yes, if you stare into the tube as you fill, you will see the dot a lot longer than if lowering each time and taking glancing looks after filling to the line(s).