Set the color chart on a table, then set the vial on top of the color chart. Look down Line up the colors and read the value.
If the color of the water is lighter than the lightest color on the color chart, then
Hold the color chart in your hand, and then hold the vial in front of it. Look through the side of the vial, line up the colors, read the value and divide it by 10 to get your nitrite value.
What I was trying to say was, if you can see any hint of pink in the water, it doesn't matter what the value is.....it's bad long term.