How to Use Water Hardness Test Strips

Here we give a step by step description of how to measure water hardness using simple test strips provided in an inexpensive water hardness test kit.

We test the hardness of the water supply for San Miguel de Allende in Guanajuato, Mexico and give the results here.

This article series explains how to measure water hardness or grains of hardness: a measure of water mineral content. We provide a table of water hardness measurements and we discuss different methods for measuring water hardness including a simple soap test.

How to Use a Simple Water Hardness Test Kit - Test Strips

We used the JNW Direct water hardness test kit strips (Amazon.com) to test the hardness level of the water supply in San Miguel de Allende, Guanajuato Mexico (Col. San Antonio) in March of 2019.

The test procedure and test results are given here.

Test Strip Measurement of Water Hardness

Test strips are typically produced from plastic, with chemically impregnated pads on the end.

These pads are designed to react with specific ions and produce a specific color change.

Once a test strip is reacted and a color is developed, the strip is then compared to a printed color chart.

The color chart is specifically designed to represent color reactions at various concentrations.

Matching the strip to the closest color match produces a concentration reading [such as those shown at the top of this page] - retrieved 12/11/2014, original source: http://www.lamotte.com/en/blog/test-factors/75-measuring-water-hardness

Sources of water hardness test kits and a description of the accuracy and utility of different water hardness measurement methods are given

at WATER HARDNESS: HOW TO MEASURE.

Steps to Use a Water Hardness Test Strip

1. Choose the water source:
   
   Incoming water hardness:
   
   if you want to test the hardness of the incoming water supply, find a faucet or water source that will draw water before it has passed through building water treatment equipment, such as at an outdoor water faucet.
   
   
   
   Watch out: do not take your water sample through a garden hose as doing so risks adding additional contaminants that are not innate in the water supply itself. Run water long enough that its temperature has dropped to a stable level, suggesting that you've obtained water from the water supply not standing water from building water pipes.
   
   Treated water hardness: If you want to confirm that your water softener is working and is producing soft water, find a faucet or water source that will draw water after it has passed through the water softener and other building water treatment equipment.
   
   
2. Select a water hardness test strip from the sealed bottle or envelope. Take care not to touch the sensing pad on the hardness test strip as you don't want to contaminate it or interfere with its sensitivity or chemistry.
3. Dip the Test Strip into the water to be tested (we used a clean glass for the water sample) for 2 seconds (or other time as directed by your hardness test kit instructions).
   
   
   
   Then shake off excess water so that the sensor tip is left wet but not with a bubble of standing water over it (as shown in our photo above.)
   
   Don't leave the test strip too long in the sample water nor in running water or you may dilute and interfere with its chemistry, thus you'd produce erroneous water hardness test results.
4. Hold the test strip level (horizontally) for 10-30 seconds
   
   to allow the chemical reaction to take place on the test strip sensor pad.
   
   
5. Read the water hardness by color comparison
   
   of the test pad on your sensor strip with the water hardness color indicating scale provided by your test kit manufacturer. These colors will vary depending on whose water hardness test kit you are using.
   
   

   We used test strips included in a water hardness test kit provided by JNW Direct and sold at Amazon to test water hardness in San Miguel de Allende, Guanajuato, Mexico, in March 2019.

   Using the test strips as directed, we compared the water hardness of un-treated water from the street water main with water hardness level after that same water supply had passed through a water treatment system that includes a water softener described separately

   at WATER SOFTENER RESIN REPLACEMENT where we describe the installation of a new water softener in San Miguel de Allende.

Un-treated water in San Miguel de Allende has a hardness level of about 27 as shown on our test strip at right in our photo above.

Water after having passed through the water softener and other water treatment equipment at our test site (Col. San Antonio) had a hardness level of about zero (at left in the photo above).

Sources of water hardness tests and kits are

at WATER HARDNESS TEST KIT SOURCES

...

Continue reading at WATER HARDNESS: HOW TO MEASURE or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• AIR QUALITY STUDY San Miguel de Allende
• ARSENIC in DRINKING WATER
• WATER HARDNESS: HOW TO DETECT
• WATER SOFTENERS & CONDITIONERS - home
• WATER SOFTENER RESIN REPLACEMENT in San Miguel de Allende
• WATER QUALITY & QUANTITY San Miguel de Allende

Suggested citation for this web page

WATER HARDNESS TEST San Miguel de Allende at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to WATER TREATMENT SYSTEMS

Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia

Ask a Question or Search InspectApedia

	HOME	ABOUT	ASK a QUESTION	CONTACT	CONTENT USE POLICY	DESCRIPTION	POLICIES	PRINT	PRIVACY
	© 2026 - 1985 Publisher InspectApedia.com - Daniel Friedman