The following chart is a general guideline for Total Dissolved Solids:

SOURCE	PPM OF TDS	*CUMMULATIVE PPM OF TDS
Initial filling of your pool	300 ppm	300 ppm
Year #1 Chemicals	450 ppm	750 ppm
Year #2 Chemicals	450 ppm	1200 ppm
Year #3 Chemicals	450 ppm	1650 ppm
Year #4 Chemicals	450 ppm	2100 ppm
Year #5 Chemicals	450 ppm	2550 ppm
Year #6 Chemicals	450 ppm	3000 ppm
Year #7 Chemicals	450 ppm	3450 ppm

*NOTE: Tap water that is used to fill the pool typically has a TDS reading of approximately 300 ppm. Each year, with chemical residue and other un-dissolved matter remaining in the pool, along with evaporation, approximately 450 ppm of TDS will be added to the pool. On average, pools in year-round climates may reach a maximum TDS reading close to Year #6 or #7, while pools in seasonal climates that winterize (and partially drain) their pools may reach a maximum TDS reading close to Year #8. This is a guideline only. You may reach your maximum TDS reading well before (if you have a consistently high bather load) or well after (if you have a consistently low bather load) these guidelines. Once TDS reaches its maximum parameters, drain the pool, either partially or completely, and start fresh. If you decide to drain the pool completely, have your local pool professionals perform a DRAIN AND CLEAN -it will be an investment versus a service call.