Calcium Booster Increases the hardness of your water and prevents damage to the technical components of your spa. Calcium hardness is expressed in mg/l (ppm) of calcium carbonate (CaCO3). The ideal level is between 100 and 200 mg/l (ppm).
For your information: 10 mg/l (ppm) CaCO3 = 1 French degree (°FH) = 0.56 German degree (°DH).
User manual:
Use 15 ml to increase hardness by 7.4 ppm per 1,000 litres of water. Turn on your spa jets and add the required amount of Calcium Booster to your spa water. Run the filtration system for 1 to 2 hours. Check the hardness again and repeat the steps if the desired water hardness is still too low.
