Water Hardness Levels

What does this mean?

*Water hardness is measured in milligrams per litre (mg/L) or parts per million (ppm) of calcium carbonate (CaCO2). This tells you how much calcium and magnesium is present in the water.

In the UK, you'll often see water hardness expressed in degrees:

Degrees Clarke (°Cl)

This is a British measure where one degree Clarke is equivalent to 1 part of calcium carbonate per 70,000 parts of water.

These measures give you an idea of how "hard" or "soft" the water is, with higher numbers indicating harder water, which means more calcium and magnesium. If you ever get your water hardness tested, the results will likely be in one of these units.

How to reduce water hardness in your home

Understanding water hardness/softness levels helps you manage the impact of water on your home or business and choose the right water treatment solutions if necessary.

Reducing water hardness in your home can significantly improve the lifespan of appliances, reduce energy costs, and make cleaning easier. One of the most effective ways to manage hard water is by installing a water softener. These systems work by exchanging calcium and magnesium ions, which cause hardness, with sodium ions, effectively "softening" the water before it enters your home's plumbing.

For those looking for a less permanent solution, water conditioners can really help. These devices don’t remove the minerals but alter their structure, preventing them from forming limescale. Alternatively, you can add water softening tablets or salt to your washing machine to help protect clothes and your machine from the effects of hard water.

For smaller appliances, like kettles and coffee machines, regular descaling with vinegar, citric acid, or a commercial descaler can prevent limescale build-up in the long run.