Hardness
All water has some degree of "hardness," which is caused by dissolved magnesium and calcium. Often, water hardness begins in your pipes or water heater because of scale formation. Water hardness is measured in grains per gallon, milligrams per liter, or parts per million.
Calcium hardness refers only to the amount of calcium in your water. You can measure calcium hardness with a special test kit - your water should have a leel of about 200 to 400 parts per million.
Temporary hardness is caused by high concentrations of bicarbonate and carbonate. This hardness is temporary because levels of these minerals fluctuate depending upon the heat of the water.
Permanent hardness is caused by too much magnesium and calcium in the water.
