Do the power levels on SWCG's overlap or are they separate? Meaning is power level 2 at 75% less output than power level 3 at 10%? I have been running at power level 2 at 60% (of course at night the % is lower due to pool pilot compensating for water temp) and first day or 2 it seemed to be maintaining it at 5.5ppm. I checked last night and it had dropped to 3.5ppm so I upped the output to 75%. What is the threshold that you would want to increase the power level and decrease the %?