A client recently had an excellent question, they wondered if we had any photos that demonstrate the disappearing logo in our CYA tests. So now, we do!
They wanted a better idea of when exactly the dot has disappeared versus just being hard to see. The CYA test is incredibly subjective and also can be very fussy about light conditions. You could run all of our other tests in a dark cupboard with a candle if you wanted to and they’d still give perfect results (but please don’t try that, well ventilated areas only please!) However the CYA test works best if you follow some simple steps and set up the right conditions for the test.
Here’s a refresher on the steps for our CYA test, with my highlights bolded.
- Rinse the CYA mixing tube with pool water.
- Fill the CYA mixing tube with pool water to the mark indicated. Allow the water to come to room temperature if pool is cold.
- Fill the CYA mixing tube to the mark indicated with CYA Detection Reagent.
- Mix the CYA mixing tube thoroughly for 30 seconds.
- Find a well lit position. Hold the CYA viewing tube at waist level and, looking down into the tube, slowly pour the contents of the mixing tube in until the logo at the base of the tube disappears. Alternatively, use the included droppers to control the dispensing rate until the logo disappears.
- Look at the scale on the side of the CYA viewing tube. The water level on this scale indicates your CYA level.
Step 4 is important! Give the reagent and the CYA about thirty seconds of mixing (stirred or shaken, we’re not James Bond) to allow the CYA to bond to the test and become visible. CYA is slower to dissolve than other chemicals, so it needs a little gentle coaxing to show itself.
Step 5 is shown in the photos below. For the best result, we like the dot in our tube to disappear, but not by adding too much liquid. Advice online can range from “when it’s just disappeared” to “fully disappeared”. The only consensus seems to be that if you can see the logo, put another drop in.
Standing with your back to the sun, so the tube is at waist height in your shadow, is the best way to standardise this test. We are very big on standardised, repeatable, replicable tests here at Clear Choice Labs, so that the only thing changing is your pool water!
If the sun is down when you test, find the strongest artificial light you can find, and using the standard, gauge how the dot disappears under those conditions. Then recreate those lighting conditions when ever you test.
Click on the pictures below to get a bigger image.