Water Hardness Indicator Strips (Johnsons U.K)
Water Hardness Test Strips
Range: 0, 50, 125, 250 and 500 ppm
50 strips per container...$15.95
The pads on these polypropylene (environmentally friendly) strips are prepared as a non-bleed system, therefore the resultant colour change will remain far longer and readable until the pads are dry.
The water hardness depends mainly on the amount of calcium and magnesium salts within the water. The total sum of these salts determines the actual water hardness. Water hardness is expressed in ppm (mg/l) CaCO3.
Generally, water is often simply classified as “soft” or “hard” water. By and large, the following values apply to these terms:
below 50 ppm CaCO3– very soft water
50 – 120 ppm CaCO3– soft water
120 – 240 ppm CaCO3 – medium hard water
240 – 360 ppm CaCO3 – hard water
above 360 ppm CaCO3– very hard water