Water hardness scale for water softener

When we experience the effects of hard water at our home, naturally we want to buy a water softener or conditioner to solve the problem. But, do you really need a water softener to solve the problem? Actually, first, you need to measure water hardness scale for water softener. If your home water contains high range of minerals, you will see some major signs-

  • Filmy spots on dishes
  • Scummy spot presents on tubs and showerhead
  • Dry skin and dull hair
  • The white spot around faucets, showerhead, and drains
  • Low flow rate of water due to a clogged pipe

In this article, we are going to describe the methods of water hardness measurement and you will be able to know a water softener is really needed or not for you.

Hardness of water definition

Water hardness is the amount of dissolved minerals like calcium and magnesium in the water. It depends on the total amount of dissolved metal rate of water. Your water may hard or soft. You may have experienced the effects of hard water on your daily water use. After washing your hands or body you may feel dry. When you use soap or hand cleaner to wash your body, it seems like there is a filmy residue left on your skin.

water hardness calculator

The hardness of water is not dangerous for health but it has some negative impact on your health, plumbing system, home appliances, and industrial heating instruments. When hard water is heated in a water heater, solid calcium carbonate deposits in it. Hard water vs. soft water

Types of hardness of water

Hardness of water measured by the concentration of dissolved metallic cations. There are two types of Water hardness is classified into two types.

  1. Temporary water hardness
  2. Permanent water hardness

1. Temporary water hardness

Temporary water hardness is caused by the presence of bicarbonate like calcium bicarbonate and magnesium bicarbonate. When these minerals dissolve in water, they produce calcium (Ca2+) and magnesium cations ( Mg2+) and carbonate (Co32-) and bicarbonate (HCo3) anions. These cations can make your water hard. You can reduce the temporary hardness by boiling your water. You can also reduce the temporary hardness level by using lime or calcium hydroxide softening process. When water starts boiling, it forms carbonate and precipitates calcium carbonate. After cooling, you will get softened water.

2. Permanent hardness of water

Heavy presence of calcium sulfate or calcium chloride and/or magnesium sulfate or magnesium chloride cause permanent hardness of water. It’s very difficult to remove permanent hardness by boiling. Hardness causing minerals do not precipitate while boiling. You can remove permanent hardness by using a water softener or conditioner. Permanent hardness is the total amount of calcium and magnesium hardness.

Permanent water hardness is the sum of permanent calcium hardness and permanent magnesium hardness

Water softener hardness chart

According to the United States Geological Survey, water hardness is classified in 4 types. You can follow the water hardness scale conversion table-


hardness in mg-CaCo3/L

Hardness in mmol/L

Hardness in DGH/°dh

Hardness in gpg

Hardness in ppm







Moderately hard












Very hard

More than 180

≥ 1.81

≥ 10.12

≥ 10.57

≥ 181

Water hardness scale measurement for water softener

A water softener is really needed or not for you, it depends on the actual hardness of your home water. You can get an idea about the hardness of your water by daily experience. But it’s important to know the actual hardness to solve the problem.

Soap test

Soap test is the easiest way to measure your water hardness. For this, you will need a small glass bottle with a tight cap, liquid dish soap, a measuring cylinder or a cup marked in ml, cc’s or ounces. Fill 1/3 of the bottle with your home water. You may take 8-10 ounces water if you measure it before pouring into the bottle.

After that, add 10 drops of pure liquid dishwashing soap and shake it for at least 10 seconds. After shaking set the bottle on the table and observe the results.

hardness of water calculation
  • If the solution creates a lot of suds quickly and the water level below the suds looks clear, then your home water is not hard.
  • If the solution creates less foam and water below the suds is relatively cloudy, you may have hard water.

Soap test for water hardness measurement does not show the exact result. For more accurate result you should follow the next methods.

Water hardness test stripe

Test stripe is a chemically treated pad and it’s the easiest and quick way to determine water hardness. Different types of test strips are available in hardware stores and online.

 You should buy a test stripe from any reputed manufacturer. Test stripe are manufactured for different purposes. So, make sure your kit tests for hardness.For the hardness test, you need to fill a glass with your tap water. Then, immerse the test stripe into the water and compare it with the given color chart.

Ideal water hardness for a water softener

If you have hard water in your home, you may notice some of the effects of hard water on your home appliances and your skin. But you may not know, how many ways it can affect your health and home. Hard water affects your life by causing many health hazard problems. If you discover hard water in your home, it needs to solve the problem as soon as possible.

Most people use water softener as its easy solution. But if you have soft or moderately hard water, you don’t need a water softener. For moderate hard water, you can use a salt-free water conditioner. You can use the triple-action poly salt-free water softener or other salt-free water oftener. For help, you can follow our buying guide.

hardness of drinking water standard in ppm

When you have hard or very hard water at your home, you should use a water softener. Water softener will remove the hard water minerals and protect your plumbing system and home appliances from the negative effects of hard water.


We are the end of our article water hardness scale for water softener. We have tried our best and we believe that our article has helped you to make your decision. Please share this article with your friends. Thanks for reading this article. Stay good.

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