The basic concept of hard water is pretty easy to explain. Hard water contains elevated levels of dissolved minerals, including calcium, magnesium, and iron. These dissolved minerals cause a number of problems in the home, such as the formation of scale, the degradation of soap performance, plumbing corrosion, and many more. But, when you start to delve into the details, it’s easy to become overwhelmed with technical jargon and hard water numbers. In this article, we will take a closer look at these topics to help you make informed decisions.

Hard Water Number Measurements

When you’re looking at water softening equipment, you may notice that they refer to water hardness in one of two ways or both, which can be confusing. These measurements are grains per gallon (gpg) and parts per million (ppm). Don’t be confused by these terms, both gpg and ppm are interchangeable, and they can be converted with a simple formula:

1 gpg = 17.14 ppm

In most cases, gpg is the common measurement, but there are exceptions, and without this formula, it’s hard to make direct water softener comparisons.

Hard Water Testing

Testing the hardness of your water with a test kit is simple, dip the strip in the water and check the color against the included hardness scale chart. Your water will fall into one of five water hardness categories depending on the gpg measurement:

  • 0-3 gpg: This indicates that you have soft water and no softening is required at this time.
  • 3-7 gpg: The water is moderately hard. You may experience dry skin, brittle hair, and spotting on dishes.
  • 7-11 gpg: This is hard water, there will be a build up of crusty scale on plumbing fixtures and pipes, and there may be red stains if excessive iron concentrations are present.
  • 11-15 gpg: This is very hard water, with all the hard water problems taken to a more extreme level.
  • 15+ gpg: This is extremely hard water, soap scum is harder to remove, iron stains may be a problem, water using appliance repairs are more frequent, and early failure is probable.

Water hardness numbers can change, and it’s a good idea to check the water hardness on a regular basis. An annual water test is a great idea for private well and municipal water users. Remember that a water treatment plant doesn’t remove the dissolved minerals that cause water hardness.

The Water Softener Range

Every water softener has a grain capacity in the 20,000-80,000 range. This indicates the softening capacity and the choices that you make will be determined by your unique situation. Some key factors include the daily water use, the number of people living in the home, and the water hardness number. Understanding these factors will determine if you need a water softener with a small or larger grain capacity to meet the demand for softer water. Check an online calculator or speak with a local water treatment specialist to ensure that you’re getting a water softener that meets your needs.

By EcoWater Systems.
EcoWater Systems of Nebraska is the largest water treatment company in the state and is a member of Water Quality Association.