If it helps .........
CYA Testing:
Proper lighting is critical for the CYA test, so you want to test for CYA outside on a bright sunny day. Taylor recommends standing outside with your back to the sun and the view tube in the shade of your body. Use the mixing bottle to combine/gently mix the required amounts of pool water and R-0013 reagent, let sit for 30 seconds, then gently mix again. Then, while holding the skinny tube with the black dot at waist level, begin squirting the mixed solution into the skinny tube. Watch the black dot until it completely disappears. If it helps, pour a little, look away, then look back and pour some more. Some people like to squirt enough solution to go line-by-line for a better feel. Once it disappears, record the CYA reading. After the first test, you can pour the mixed solution from the skinny view tube back to the mixing bottle, shake, and do the same test a second, third, or fourth time to instill consistency in your technique, become more comfortable with the testing, and validate the CYA reading. If you are still questioning your own results, have a friend or two do the same test 2-3 times. Share your results only after everyone is done to see if you came up with the same average results.