This test offers two ranges.
Low range: 0.2 to 10 mg/L (ppm) as nitrate
Medium range: 2 to 100 mg/L (ppm) as nitrate
Clean test vial and scoop after use. Store this kit in a dry place.
- Fill the test vial with 1 ml of water.
- Add 4 drops of NO3-1.
- Add 1 level scoop of NO3-2 powder (compress this powder against the inner side of the powder container). Swirl gently (DO NOT SHAKE) for 30 seconds. Let stand for 3 minutes.
a. Medium range: Place test vial on white part of color chart and compare colors looking from the top. Use diffuse daylight when comparing colors. If the color corresponds to a value lower than 10 mg/L nitrate, then it might be better to compare colors as shown for the low range.
b. range: If the medium range color comparison gave a reading lower than 10 mg/L, then you can use the low range procedure. This will increase accuracy. Compare the color for the low range procedure by looking through the side of the test vial. Hold the white part of the color chart firmly against the opposite side of the test vial. Use diffuse daylight when comparing colors. The color is amplified by approximately 10-fold so you have to divide the color chart values by 10.