We call it the Pool House, and it's a simple diagram that clearly shows you the chemical structure of a healthy pool. Think of the various elements within your pool water like the different components you'd use to build a house. The foundation for crystal clear water begins with a total alkalinity of 70 to 140 ppm (ideal range varies based on pool finish). Moving up to the first floor, pH levels should be maintained as close to the ideal of 7.4 as possible. A proper chlorine level of 2 to 4 ppm forms the second floor, and a stabilizer reading of 40 ppm tops everything off as the roof. Calcium hardness is the walls which keep the floors in place, and should be maintained at 200 to 400 ppm. So keep this structure in mind when testing your water – it's an easy way to clearly picture the components of a perfect pool.

View the full size Understanding Water Balance portion of our "Pool Care Tips" manual.