If you live in Adelaide, Perth, regional Queensland, or almost anywhere fed by bore or river water, there is a high probability that your water hardness is above 100 mg/L of calcium carbonate. International convention classifies anything above 120 mg/L as hard water, and the Australian Drinking Water Guidelines note that scale problems become significant above 200 mg/L.
These are not small numbers. They represent a meaningful mineral load depositing on your hair and scalp with every shower.
A rough guide by region
Water hardness varies significantly across Australia. Here is a rough breakdown by region, based on data published by Australian water utilities:
- Adelaide and South Australia: 120 to 180+ mg/L. Hard to very hard. The hardest capital-city water in the country.
- Perth and Western Australia: 100 to 200 mg/L. Moderately hard to hard.
- Regional Queensland (Townsville, Toowoomba, inland towns): 150 to 300 mg/L. Hard to very hard, particularly on bore-fed supplies.
- Brisbane and the Gold Coast: 80 to 150 mg/L. Moderately hard.
- Darwin and the Top End: 80 to 150 mg/L. Moderately hard.
- Sydney and Canberra: 40 to 60 mg/L. Generally soft.
- Melbourne and Hobart: 10 to 40 mg/L. Among the softest city water in the world.
Why geography affects your hair more than genetics
Hair loss, thinning, and texture issues are often attributed to genetics, diet, or stress. These are real factors. But if you have moved from a soft water area to a hard water area and noticed your hair changing, your water supply is the most likely explanation.
The same applies in reverse. People who move from Adelaide to Melbourne often report their hair improving within weeks. Not because of the fresh air. Because they have removed 150 mg/L of calcium and magnesium from their daily shower.
What you can do without moving house
You cannot change your postcode's water supply. You can change what comes out of your shower head. A three-stage filtration system removes the calcium, magnesium, and chlorine before they reach your hair. Water pressure stays the same. Installation takes 60 seconds, no tools required.
If you are in Adelaide, Perth, or regional Queensland, this is not an optional upgrade. It is the most impactful single change you can make to your hair care routine, and it costs less than two months of the average premium shampoo spend.