To remove these minerals, you need a water softener. The U.S. Geological Survey uses the following ranges of measurements to classify water into hard and soft water: Hard and Soft Water Classification. In your home, here is how to tell if your water is hard or soft. GPG is the most common water hardness measurement type and it is essentially a way to calculate the amount of calcium hardness. Hard water … Here are a few: Hard water does not lather with soap. If your water is slightly hard or soft then it will have up to … Hard water vs. soft water—this is one of those boring topics you can go far in life without ever really figuring out (especially before you own a home/set down roots). You will not know if the water is soft or hard by just looking at it. Common in laundry products, water softeners are a wide range of products and devices that remove calcium buildup and the like from water. It all depends on the rock types found in that region. Soft water is surface water that contains low concentrations of ions and in particular is low in ions of calcium and magnesium.Soft water naturally occurs where rainfall and the drainage basin of rivers are … Basic softeners … It has to go through a test. A single-number scale cannot describe hardness of water accurately because the behavior of hardness depends upon a variety of factors such as minerals in the water, pH and temperature.