If you want to know my opinion on it watch this quick video:
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0:00 – Introduction: Printout of instructions here
2:05 – Rinse with the same water your testing
2:35 – How to create a diluted sample (for testing nitrates 5-50ppm)
5:49 – Mixing test water and reagents A & B
8:30 – Extract mixture then run 10 mL of it through filter
10:36 – Clean cuvette turn on checker and get the zero reading
11:18 - Put reagent C in and shake for 2 minutes
12:15 – Put back in the checker and start its 8 min timer
13:10 – Read the checker (multiply by 10 if you diluted the mixture)

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