Have a fleck 7000sxt. Started getting less soft water after about 6 years or so. Started by rebuilding the valve with new seals which helped, but then water got hard over time. I replaced the resin with 10%, but still no change. I did the test where I ran the brine draw cycle and tested for salinity at the drain tube and water was not salty and showed 1.0 on refractometer. I think that means my seal is still good. Brine draw and fill both happen correctly. Any reason I'm still not getting soft water?