Macherey-Nagel
On demand
Macherey-Nagel test strips for dissolved calcium, in one presentation.
91324
A semi-quantitative test strip for dissolved calcium. Dip it, wait the stated time, and compare the pad against the colour scale on the tube.
Calcium is most of what people call hard water. Too much and it scales heaters, kettles and membranes; too little and the water turns aggressive and starts dissolving the plumbing and, in a pool, the plaster.
A strip gives a range, not a figure. That is enough for the great majority of decisions — dose or do not dose, discharge or hold, keep running or stop — and it gives the answer where the sample is, in about a minute, with no instrument to calibrate and nothing to carry back to a laboratory.
When a number has to be defensible — a regulatory report, a dispute, a limit you are close to — a photometer or a laboratory method is the right tool. The strip's job is to tell you whether you need one.
Calcium alone is not total hardness — magnesium makes up the rest, and the two behave differently in scale.
Supplied in one presentation.