How to Test for Hard Water

You can do a fairly reliable unscientific test to see if you have a problematic level of hard water in your home by doing the following test with liquid dish washing soap:

Take a clean empty plastic bottle having a cap (such as a clean, clear pop bottle);

Remove the cap;

Open your tap water faucet and fill the bottle with about a half-cup of water (8 to 10 ounces);

Add 10 drops of dish washing liquid;

Shake well;

If the soapy solution foams up quickly you are good and the water is not hard;

If it does not foam up but instead creates a milk-curd-like or soapy film on the water surface then the water is likely hard.

If you have hard water scale build-up on your shower door or white scale on your faucet aerator, this is also another indicator your water is too hard.

You can also send a water sample out for testing to a certified water testing laboratory. Hard water is anything above 1 grain of hardness per gallon. (A grain of hardness is an amount of calcium and magnesium equal in weight to a kernel of wheat).

• Less than 1.0 = Soft
• 1.0 - 3.5 = Slightly Hard
• 3.5 - 7.0 = Moderately Hard
• 7.0 - 10.5 = Hard
• Over 10.5 = Very Hard

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