Description HACH TEST STRIPS TOTAL HARDNESS 0-425PPM PK50 Water hardness is caused almost entirely by calcium and magnesium ions. Other di- and trivalent metals have a similar effect, but usually are not present in high enough concentration in potable waters to cause problems. Hardness increases soap consumption in laundries and causes scale in boilers. Number of Tests 50 Parameter Hardness, Total – as CaCO3 Range 0 – 425 ppm Range 2 0 – 25 gpg Smallest Increments Intervals: 0, 1.5, 3, 7, 15, 25 gpg Smallest Increment Steps Steps: 0, 25, 50, 120, 250, 425 ppm
