How to Test for Hard Water

on September 19, 2019 contaminants household

There are several ways to test for hard water in your home if you suspect it might be the cause of your spotty dishes, scaly pipes, scummy tubs, or itchy skin.

Methods for Testing Water Hardness


Dish Soap Test

Get a clear, clean, empty bottle with a cap. Fill the bottle one-third full of water and add a few drops of liquid dish soap. Make sure you use pure liquid soap, not detergent. Put the cap on the bottle and shake the bottle vigorously. Did fluffy bubbles form on top of the water, or is the water just cloudy? If it’s the latter, you have some level of hard water in your home. What level of hard water do you have? The dish soap test can’t tell you that.

DIY Water Hardness Test Kits

There are a variety of different types of water testing kits available at your local hardware store. One of the simplest to use is test strips. Dip the test strip into a sample of your water, its color will change according to the hardness of your water. A color chart on the packaging tells you what each color means. You'll also want to look at the grains per gallon of water to determine the level of hardness. This can be calculated by dividing the mg/l by 17.1. Both results are used regularly to determine how to treat the water.

There also are products available that look like hand-held digital thermometers. According to Water Filter Magazine’s review of water test kits, they are generally the most accurate but tend to be more expensive. 

Call the Water Company

If you are on public water, you can call the water utility and ask for the water quality report for your area. While the report won’t be specific to your home, it will give you an idea about water quality in your area. Look for calcium carbonate on the report and see how many milligrams per liter (mg/L) is in your water. The higher the number, the harder your water. Here’s the scale used by the U.S. Geological Survey:

- 0-60 mg/L – Soft

- 61-120 mg/L – Moderately hard

- 121-180 mg/L – Hard

- 181 mg/L and up – Very hard


Use an Independent Laboratory

An independent water testing laboratory can give you a detailed report on your water quality. If you have a well or private water source, you are responsible for assuring your water is safe and the EPA recommends routine water testing.

Leave It for the Pros

Your Indy Water Pros at Advantage Water Conditioning also provide on-site water analysis for hardness, iron, and sulfur. We provide this service at no charge. For more problematic water, we may recommend the county board of health conduct an in-depth water analysis. Talk to us today to learn more.

Speak to an Advantage Water Specialist