Swimming Pool Water Treatment Guide - Swimming Pool Calcium Hardness Levels

Total hardness in swimming pool water is basically the total minerals in the waters content. Elements that make up this are calcium, iron, magnesium, manganese and some others. Elements such as these are all in the water that is used to fill the pool, the levels also increase when using pool chemicals regularly such as chlorine with calcium hypochlorite. It is the calcium hardness levels we are interested in.

250 - 350 ppm is the ideal range for calcium hardness levels in a swimming pool.

Low Calcium Hardness - Water can become corrosive if calcium hardness levels are to low which will result in surfaces of the pool becoming etched. Swimming pool walls and floor will stain as metals corrode which also includes the pools equipment such as pipes and pumps and the connections to them.

Increasing Calcium Hardness Levels - Calcium chloride is best to use as this will easily increase low calcium hardness levels. Once you know how much calcium chloride to add to your pool you should split it into three parts. After the first part has been added you should circulate the pool water for a minimum of four hours. After this test the water again and repeat the process until your calcium hardness levels are correct.

High Calcium Hardness - Pool surfaces will form scale, filter and pipes will clog when calcium hardness is too high causing filtration and water flow to decrease in efficiency. This will cause water to become cloudy and swimmers will get eye irritations.

Reducing Calcium Hardness Levels - Unlike increasing levels it can be very hard to lower them. You will need to either add chemicals to help keep calcium in solution to help prevent it depositing, or you can remove and replace some or all the pools water. It is recommended that you contact a pool professional if calcium hardness levels are very high.