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How to Test for Hard Water in Your Home

Joe KnowsHard water, contrary to what the term sounds like, is not ice. The “hard” refers to a high mineral content. There are many arguments for and against the use of hard water in homes. It's a common issue in homes and is easy to test for. Here’s how.

Before You Test

If you are in the market for your first home and have never dealt with hard water, educate yourself on what it is and the issues that come along with it. 

When certified water testing facilities measure the amount of minerals in a water sample, anything with more than one grain of hardness per gallon qualifies as being "hard." defines a grain of hardness as the “amount of calcium and magnesium equal in weight to a kernel of wheat.” 

What problems come with hard water? Some argue that hard water does not taste as good as soft water. It also cuts back on the efficiency of soaps and detergents, and causes unsightly mineral buildup. Bathing in hard water can leave an icky film of minerals and soap scum on your skin.

If a home you are considering buying does indeed have hard water, don’t worry. One easy solution is to install water filters for the whole house.

The Easy Bottle Test

The at-home test for hard water is super easy. Even if you have lived in the same home for decades, discovering that you have hard water can answer some questions you had about why you always have to use so much fabric softener or why you get spots on your dishes so often.

– First, find an empty 16-ounce water bottle with its cap. You'll also need dish soap.

– Put about 1/2 cup of tap water into the bottle. Add 10 drops or so of the dish soap. Tightly close the bottle.

– Vigorously shake it.

 –If soapy suds form quickly and linger in the bottle, your water is nice and soft. Hard water will look milky, and suds will disappear quickly if any form. A film may also appear.

Super simple, right?

Watch the video:

Look for Buildup


Image via Flickr by Graeme Maclean 

Another quick way to see if you have hard water is by taking a close look at your sinks, tubs, and faucets. Mineral buildup will form in these places. Check the aerators of faucets as well. 

If you have hard water stains or see them in a home that you might buy, you can get rid of the stains in a few steps.

– Prepare a 50/50 mixture of water and white vinegar.

– Dip a rag into the solution and wipe the affected area. You may need to leave the rag on the area for a few minutes before you wipe. The worst spots will take several applications to clean thoroughly.

– If you have large spots, such as on glass shower doors, put some of the mixture into a spray bottle. Go over the area a few times, spraying repeatedly.

– You also want to get rid of buildup in aerators, so soak them in vinegar.

Once everything is clean, you can welcome your new filtration system and not worry about having to deal with those ugly spots ever again.

The Scientific Test

You can send a water sample to a lab to confirm the hardness of your water and tell you exactly how hard it is. Or, you can take a short drive to the nearest hardware store or home center and grab an at-home test kit. The strips that come in the kit will give you a fairly accurate reading on the hardness of the water in your home.

The kits come with other testing strips as well. You can see if your water has too much iron or nitrate, or if it is acidic. Low levels of water hardness are usually more of an inconvenience than anything else, but if you have very hard water or find that your water has other problems, it is all the more reason to invest in a filtration system.

Water is the liquid of life – for hydration, for cleaning, for cooling. Water with icky or unhealthful contaminants can put a damper on more than one aspect of your life. A simple test will let you know if you need to take action to clean up your H2O.