Water Hardness
Water hardness plays an important role in daily life and a wide variety of industries and applications. Hard water can even adversely affect taste and appearance of the food.
Hard water inhibits the lathering of soap, so more detergent has to be used in hard water in order to achieve the same cleaning results as in soft water. Additionally, hard water may cause calcification and can thus damage machinery, appliances, pipes or heating units.
In many industries, water hardness is an important parameter in process control and has to be monitored constantly. Some examples of industries include the textile industry, dyeing factories, large scale laundries, water works and fish farming and aquaculture.
That is why, the water quality and water hardness is very important both in the industry and in daily life! It is important parameter and has to be monitored constantly.
Measures of water hardness
General guidelines for classification of waters are:
German Hardness d ºH | French Hardness f ºH | CaCO3 (mg/L or ppm) Calcium Carbonate | Evaluation |
0 – 4 | 0 – 7 | 0 – 71 | Very Soft |
4 – 12 | 7 – 21 | 71 – 160 | Medium Hard |
12 – 17 | 21 – 30 | 160 – 213 | Hard |
> 17 | more than 30 | more than 213 | Very Hard |
NOTE: Other organizations may use different classifications.
Hardness conversion factors
1 German Hardness (°dH) =1.78 French Hardness (°fH) = 17.8 mg/L CaCO3
Measuring the Total Water Hardness with AQUAX®P Test Strips
AQUAX®P test strips are for the simple, quick and easy determination of water hardness. The easy dip – read procedure and the color changes from green to reddish ensure reliable results within few seconds.
AQUAX®P test strips are with 5°dH (German Hardness) interval gradations and packed as 100 strips in a safe tube.
TEST METHOD
The easy dip- and-read application provides reliable results within few seconds. Dip the strip pad into the liquid to be tested for 1 second and match the color of the pad to the diagram on the box label to obtain the water hardness value.
Shelf-life and storage