There are two types of calcium scales that form in pools: calcium carbonate and calcium silicate. Calcium carbonate is white and flaky, and it’s fairly easy to take off. Calcium silicate, in contrast, is white-grey and more difficult to move.
When talking about ‘calcium hardness’ levels in regards to your pool, it applies to the measure of total hardness of dissolved minerals such as calcium and magnesium. The recommended level is between 200-400 ppm.
High levels may result from pool water evaporating and increasing the concentration of calcium in the remaining water as it leaves the mineral behind. Also, some chlorine chemicals contain high levels of calcium and can make the problem worse. Switching your chlorine sanitiser to one that contains a smaller amount of calcium can help reduce the chances of problems with calcium hardness levels.
Prevention is better than cure
You can prevent future calcium build-up with the following measures:
- Maintain the pH at the recommended level for your pool, because pH can have a bigger effect on calcium scaling than calcium levels do
- Install an automatic pool cover that will reduce water loss, because evaporation can leave calcium residue
- Remove calcium through a reverse osmosis water treatment
So how do you know when the calcium hardness levels of your pool are too low or too high? Taking a water sample to your local Swimart store will ensure a correct diagnosis and treatment. Give us a call on 1300 991 104 and we'll help find you a solution.