Pure-Spa Hardness Increase - 1kg (Note you may receive an alternate label design)

Calcium Chloride used to increase the Calcium Hardness in your pool.
Too little Calcium can cause surface damage to pool surfaces, but too much causes scaling.

It is necessary to keep control of the Calcium hardness in pool and spa water. Too much Calcium will cause scaling of pipes, valves, pumps and especially heat exchange equipment. Too little Calcium and pool construction materials such as tiles and cement will tend to dissolve in the water causing surface damage.

Various "ideal" Calcium levels are quoted by pool equipment manufacturers and you should seek their guidance. These are likely to be in the range of 100 to 500 parts per million. Typical levels would be 120 p.p.m for Plastic Pools and 220 p.p.m. for tiled and marblesheen pools.

If the pool equipment manufacturer advises raising the Calcium content: -

1 Kilo of Hardness Increase will raise the Calcium content of 20,000 litres of water by 90 parts per million.

If you need to reduce the hardness, then fresh water needs to be added, provided of course that it doesn't have too much Calcium in it. In this case SCALE CONTROL should be used to sequester the Calcium.

Note: If you are using Calcium Hypochlorite as a Sanitiser then you are already adding Calcium to the water. You should also know the hardness of your water supply. Your water supply company can tell you this. If your kettle regularly "furs up" then your water supply has got a lot of Calcium already!