The strips are fairly easy to use but the difference between the different hardness levels is quite mixed. I think the best you can do is determine if your water is very hard or not. My city water company puts the hardness at about 20 gallons per gallon, but these strips don't give me the slightest idea, not even an approximation. The box has a color key and a separate printout. The hues between the two are slightly different, which helps even less.
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