Hard and Soft Water – What Is Your Taste

We can convert hardness to grains per gallon by using 17.1 ppm which is equal to 1 grain CaCO 3 / gallon. Thus, the calculation would be: Thus, the calculation would be: 220 ppm * (1 grain per gallon / 17.1 ppm) = 12.86 grains per gallon. ................
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