64oz.org may earn commission for purchases made through the links posted on this page.

Hard Water vs Soft Water

by Peter Lombardi

Quality Specialist, Consultant

> 4 min read

Cropped shot of a woman washing her hands at a bathroom sink

The water in the public water supply is not pure H2O because it contains additional minerals and chemicals. Depending on the levels of specific minerals, water is hard or soft. You may not notice the difference between hard and soft water unless the mineral concentrations are present in substantial amounts.

However, many consumers are increasingly aware of what they put into their bodies. Because everyone needs to drink to live and stay healthy, it’s unsurprising consumers are interested in the makeup of their water supply.

Knowing whether hard or soft water is present in your water supply is vital when deciding if you are happy with the water quality coming through your faucet.


Dirty faucet with stain and limescale in bathroom

Differences Between Hard Water and Soft Water

Hard water has an excessive presence of magnesium and calcium. These are naturally occurring minerals crucial for human health. However, it is unnecessary to have them in your water supply. As calcium and magnesium levels increase, so does the ranking on the hard water scale. 

In contrast, soft water has low levels of calcium and magnesium. Soft water also may have higher levels of sodium than hard water. Sodium is also essential for human health, but people get most of their intake from foods rather than their water supply.

How to Tell if Water is Hard or Soft

You should receive a yearly report from your water supplier stating what minerals are in your water supply. You could also have a contractor test your water to determine the hardness level. However, there is no need to go to extra expense when inspecting your water quality. There are some tell-tale signs that your water is either hard or soft. 

Hard Water Signs

If you have a hard water supply, you may feel a slimy film on your hands during washing. When calcium mixes with soap, it forms a curd-like substance, making it harder to rinse the covering off your skin. You may also notice your skin feels drier and that your hair becomes brittle after washing in hard water.

When hard water comes into contact with household surfaces such as sinks and shower trays, it can leave a chalky white substance behind. These stains are calcium deposits, and you may need to scrub for longer to clean your surfaces. 

Hard water signs can appear on your plates, glasses, and cutlery. The calcium deposits appear as spots on your dishware. Clothes may also look grubby because the minerals cling to the fabric and make it easier for soil to attach to your laundry.

Low water pressure can also be an indication your home has a hard water supply. As the calcium and magnesium flow through your pipework, they can attach to the surfaces. When the deposits become large enough, they inhibit water flow and reduce your water supply pressure.

Soft Water Signs

To identify the difference between hard water vs. soft water, try tasting it. If you notice a slight taste of sodium in your tap water, you probably have a soft water supply. When bathing, it is easier to get a good soapy lather using soft water, and your water pressure should be strong as there are no blockages in the piping. 

Laundry tends to keep its colors for longer when using a soft water supply because the detergent can form a lather, and there are no excess minerals to make your clothing look grimy.

Advantages and Disadvantages of Hard Water

Scientists continue their research to determine if there are beneficial health effects of drinking hard water. Calcium and magnesium are essential minerals for human health, aiding with bone density, digestive enzyme function, normal muscle function, and electrolyte imbalance. 

However, the levels of these minerals in hard water are still relatively low, even though they exceed the concentrations present in soft water. There is some evidence to suggest hard water may have a dose-dependent protective effect against cardiovascular disease, but more research is needed.

There are also studies indicating hard water can adversely affect human health and increase the risk of kidney stone recurrence. Scientists need to conduct more research before determining whether hard water is beneficial or potentially harmful.

Aside from health concerns, hard water deposits on your surfaces can have a financial impact. You may need to spend more on cleaning detergents and more time scrubbing the deposits. If you notice your clothing becoming grubby, you could end up paying more than usual on new shirts and pants. 

There is also the more substantial problem of a hard water build-up on your pipes. When the magnesium and calcium deposits break away from the piping surfaces, they could take small pieces of the material with them as they travel. Eventually, you may need to pay for expensive pipe repairs or replacements.

If you have concerns about the effects of hard water on your health and property, using soft water can be an excellent alternative.

Advantages and Disadvantages of Soft Water

One of the most compelling arguments for soft water in the hard water vs. soft water debate is reducing pollution from calcium and magnesium. Although these minerals are present in soft water, it is at much lower levels. 

When using soft water, there is no scaly build-up on your surfaces, and there is no need to spend extra money on soaps and detergents. 

The levels of sodium are small in soft water, so there is little risk to human health. The US Environmental Protection Agency (EPA) provides regulations on safe mineral content levels for water suppliers. 

If you are on a sodium-restricted diet or prefer to have the information for peace of mind, you can ask your supplier how much sodium is in your water supply. There is also no detriment to having lower concentrations of calcium and magnesium in your water, as you can obtain these nutrients from foods and other drinks.

Concept idea with glass of water and test or indicator of water hardness

The Bottom Line

If you have a hard water supply, you might want to invest in a water softener to obtain a soft water supply. You could benefit from more hydrated skin, fewer calcium deposits on your household surfaces, and not spend as much money on cleaning products and replacement clothing.

Peter Lombardi

About the Author

Peter is a Los Angeles based water quality specialist, and works as a surveyor for businesses and communities looking to be informed and active about the quality of their water. He shares his expertise with 64 oz. to ensure everything is accurate, and to prevent the spread of misinformation about water contaminants.