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How to test nitrate-nitrogen (NO3-N) using the Kyoritsu packtest

What is it? Nitrates are a specific form of nitrogen that are formed after nitrites have been exposed to nitrifying bacteria. Nitrates (NO3) are bioavailable, making them an important source of nitrogen for plants.

Why is it important? Algae and other aquatic plants use nitrates as an important source of food. However, excess nitrates in water can make it difficult for aquatic insects and fish to survive. If we do not manage levels and understand the nitrogen cycle, algae growth can go unchecked, reducing dissolved oxygen in the water. This directly impacts aquatic life.

Learn more

About the Kyoritsu test

How to test

  • Take one tube out of the bag with the green label (Nitrates). Pull out the plastic pin. Squeeze out the air from the tube. 
  • Holding the squeezed tube, put it into your sample and release to suck up water (like a baster!). Your sample container should be half full.
  • Invert at least 5 times to allow the reagent to dissolve in your sample. Set your timer for 3 minutes.
  • Compare your results to the comparison chart. If the results are in between, record the halfway point.

Comparing results

Use the comparator provided with your kit and take your time. You're looking for if values are low/medium/high, rather than precision (not possible with this type of test)! Do not compare with a screenshot or photograph, as lighting will make it inaccurate.

Interpreting results

Normal levels depend on your location. The following values apply to the UK:

  • 0.2 - 0.05 ppm: Low/Normal
  • 0.05 - 0.1 ppm: Medium
  • 2 - 5 ppm: High
  • 5 - 10 ppm: Very high

Watch the protocol in action


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