Test Your Water in One Evening

Four ordered steps, one evening, and a recorded number in mg/L of CaCO3.

Start with what you can see and smell. Cloudy water, a chlorine smell or an oily film point to issues other than hardness, and knowing that first keeps the later steps from being read the wrong way.

Next, inspect the kettle. After a week of normal use, tip it out and look at the scale layer on the element; a visible ring within weeks places the water in the hard or very hard band before any strip is opened.

Then run a strip test. Dip one strip per sample, hold it for the time printed on the bottle, match the colour against the band chart, and record the result in mg/L of CaCO3 immediately — comparing from memory later is where most home tests go wrong.

Finally, read the utility report. Your water provider publishes hardness figures, and placing that number beside your strip result either confirms the band or shows that a second strip on a fresh sample is worth running.

A handheld TDS meter can be used as a quick cross-check: it estimates total dissolved solids in mg/L from the electrical conductivity of the water. It reflects all dissolved ions together, so treat it as a rough figure rather than a hardness reading.

• Step 1 — look and smell: rule out chlorine, cloudiness and film.
• Step 2 — kettle check: measure the scale layer after a week of use.
• Step 3 — strip test: dip, wait, match, record in mg/L of CaCO3.
• Step 4 — utility report: compare the published figure with your strip result.
• Cross-check — TDS meter: conductivity in mg/L, rough only.

Further reading

• The Hardness Scale Explained
• Filter Types Compared