Physical Properties
Hardness
Mainly calcium and magnesium content, common in London water.
What is Hardness?
Hardness reflects dissolved calcium and magnesium, largely determined by local geology.
Why test for it?
Hardness explains limescale behaviour and is relevant to how some filtration technologies perform over time.
Where can it come from?
- Chalk and limestone geology
- Blending of different source waters
How is it measured?
Determined by ICP or titration, reported as mg/L CaCO₃ or in mmol/L.
What does my result mean?
Hardness is a water characteristic rather than a contaminant, and is used to contextualise other results.