You hear the phrases “hard water” and “soft water” all the time.  What do they mean?

A water’s hardness is determined by the amount of calcium carbonate (CaCO3) in the water.  This is a naturally occurring mineral found in items such as chalk, limestone, and marble.  It is measured in grains per gallon (GPG).  The higher the GPG, the harder the water.  Lake Michigan water measures around eight grains per gallon, which makes it medium-hard.

Here are some of the pros and cons of hard water.  First the pros:

Now the numerous downsides:

For all these reasons, many people elect to install a water softener.  Here are a few general points about how water softeners work: