There’s a lot of confusion about the terminology used to describe different water softeners. One person’s water softener is another person’s water conditioner. Then there are all the different terms used for saltless water softeners. You’d think that there would at least be a standard definition for soft water. But as it turns out, the question What is soft water? elicits different answers from different people.
So, What is Soft Water?
Rainwater is soft, and also a bit acidic. As it soaks into the ground and makes its way through earth and rock, it dissolves minerals like calcium and magnesium. Water that contains a certain level of these hard water minerals is considered hard. According to the water hardness scale developed by the United States Geological Survey, the standard definition of hard water is water that contains 7 grains per gallon (gpg) of hard water minerals.
According to the same table, soft water is water that contains less than one grain per gallon of these minerals. The confusion comes from the fact that there’s obviously a large gap between hard and soft water. In other words, just because water isn’t technically hard, doesn’t mean it’s soft, either. There are a lot of classifications on the water hardness scale that fall in between these two extremes.
Having said all that, most people don’t think about hard water and soft water this way. It’s safe to say most people think of hard water as water that tends to cause problems, and soft water as water that doesn’t.
What is Softened Water?
Another term you might run into is softened water. This is water that has been treated with a conventional water softener in a process called ion exchange. Basically, the water softener removes the undesirable hard water minerals and replaces them with sodium (which is why conventional water softeners require a regular supply of salt).
Note that softened water is not the same thing as soft water. Softened water has been treated with a water softener, whereas soft water may be naturally occurring.
What is a Water Softener?
Now back to the water softener vs water conditioner debate. There’s really no widely agreed upon definition of these terms. Water conditioner is considered a general term that can apply to both water softeners and other water treatment systems. However, to some people, a water softener must reduce hard water minerals to below the level of one grain per gallon. To others, any system that removes minerals qualifies as a softener. Finally, many soft water systems call themselves softeners because they’re designed to eliminate hard water problems, even if they don’t actually remove any minerals from your water.
All of this is really just semantics. The bottom line is that the question What is soft water? is less important than What is hard water? If you have hard water, then you’re vulnerable to a number of problems such as soap scum and limescale. And if that’s the case, then any system that helps prevent these problems is the solution – regardless of what it calls itself.