Water, with exception to distilled water, contains dissolved salts (magnesium and calcium carbonates). The concentration of these salts determines the water hardness, which can be expressed in calcium carbonate or magnesium carbonate. The sum of these two represents the total hardness level.

The presence of dissolved salts is due to the fact that water often comes from underground sources which are in turn made up of rain water filtered through deep ground layers. Rain water eventually reaches a waterproof flooring and forms a natural tank which is also called the water bearing stratum.

By passing through the various layers of soil and rock, rain water dissolves some of the mineral substances. Hardness is a consequence of the type of rock layers which the water passes through and of its permanence in the water bearing stratum.

In addition, this parameter is also related to the phenomenon of pipe rusting in water heating and cooling systems, reverse osmosis and demineralization plants.

HANNA® offers two different meters to measure magnesium and calcium, results are expressed in CaCO_³ equivalent.

Order Information:
HI 96719 is supplied with 2 cuvets, battery and instructions.