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Hard Water Testing

If you are on a municipal water system, the water supplier can tell you the hardness level of the water they deliver. If you have a private water supply, you can have the water tested for hardness.

As a guide, 60% of the UK population live in a hard water area.

Most water softener companies will be able to supply you with a free water testing kit.

Once you've tested your water supply, the hardness of your water will be reported in grains per gallon, milligrams per liter (mg/l) or parts per million (ppm). One grain of hardness equals 17.1 mg/l or ppm of hardness.

Classification mg/l or ppm grains/gal
Soft 0 - 17.1 0 - 1
Slightly hard 17.1 - 60 1 - 3.5
Moderately hard 60 - 120 3.5 - 7.0
Hard 120 - 180 7.0 - 10.5
Very Hard 180 & over 10.5 & over