Fairly new to Salt Pools (2 yrs running). Within the last 2 months of heavy pool use, splashout, evaporation, etc. I have not added an ounce of salt. Generator is set at 35% for summer months. TC runs 4-5 constant. Readout on my PS-8 has not changed from 3500 since March. Salt test strips indicate simlar results. Is this common????