What is calcium hardness?
Calcium hardness is a measure of the amount of lime dissolved in water. Calcium hardness coming out of your tap water is considered soft if it is below 100 parts per million or hard if above 400 parts per million. As calcium hardness increases in swimming pools, scaling on the tile (see picture above), the interior finish of the pool, and filtration equipment occurs.
How do I detect calcium hardness in my pool?
Calcium hardness can be detected in swimming pools by noticing scaling (see sample image above) on the following:
  • Scaling on the swimming pool tiles.
  • Scaling on interior finish of the swimming pool.
  • Scaling on spillways, and decorative water features.
Scaling occurs when the levels increase, which is also a sign that the water should be changed.
How can I test for calcium levels in my pool water?
Taylor Swimming Pool Test Kit

Calcium Test Kit

To accurately test calcium hardness, you will need to purchase a drop based test kit. Using a drop based test kit to titrate will give you the most accurate measurement of calcium in your pool water.

Do not confuse calcium hardness with TDS, as calcium is only one component of TDS. A drop based test kit will have a pronounced color change once you achieve the end point, providing the true calcium hardness level.

Ways to Lower Calcium Hardness

When calcium levels are too high in a swimming pool it is recommended to drain the pool. Any time you remove water from a swimming pool you run the risk of ruining the interior finish.

Reverse Osmosis (RO) filtration lowers calcium levels and is by far the most effective way as the water levels in the swimming pool don't change.

Puripool™ Process