The HI719 Checker®HC is a simple, accurate,
and cost e$ective way to measure
magnesium hardness. The HI720
Checker HC is a simple, accurate, and cost
e$ective way to measure calcium hardness.
The HI719 uses an adaptation of the
Standard Methods for the Examination
of Water and Wastewater, 18th edition,
EDTA colorimetric method. The reaction
between magnesium and reagents causes
a reddish-violet tint in the sample.
The HI720 uses an adaptation of the
Standard Methods for the Examination
of Water and Wastewater, 18th edition,
Calmagite method. The reaction
between calcium and reagents causes
a reddish-violet tint in the sample.
