Water hardness – bulk test

What is hard water?

The hardness of water has a direct effect on the ability to form a lather when mixed with soap. This means that you will end up using more soap to achieve the same froth and get the same cleaning effect as in a soft water area. It also leaves a soap scum which does no occur as much in softer water areas. Typically soft water is found in areas such as Cornwall where the underlying rock is granite. In areas such as Hampshire the the water passes through chalk deposits on its way to aquifers, and this is where the additional calcium ions that make the water hard are picked up.

Testing for water hardness

As indicated above, testing for water hardness is relatively simple. All you need is a sealable and see through container such as an empty drinks bottle. Half fill it with water and add a few drops of washing up liquid, close the lid and shake vigorously. The less foam produced and the more milky looking scum on the surface the harder the water you have.

Some forms of hard water can be ‘cured’ by boiling the water, but this only works if the Calcium present is in a hydrogen carbonate form. Other sorts of calcium salts mean that the water is permanently hard and will not be softened by boiling.