The (water) hardness of drinking water or mains water in the Netherlands is generally expressed in German degrees. Hard water means a high level of calcium and magnesium.
Drinking water companies in the Netherlands use the following (German degrees dH) scale: 0–4° dH very soft, 4–8° dH soft, 8–12° dH average, 12–18° dH quite hard, 18–30° dH hard.
The average hardness of fresh swimming water is between 5.5° and 14.5° dH, which corresponds with the values between 100 and 250 ppm.
When the lime in the swimming water is in balance, this means that there is no limescale deposition or turbidity, or that no sedimentation of lime can take place. The lime is then entirely dissolved in the swimming water.
If you require further information, then contact our Starline sales team.