Sorry to bring this up from the dead.
I live in a place that I cannot bypass the softened water (Townhome). Do I just have a long hard road ahead of me? An RO unit was suggested, but I rather not have to go down that road unless I truely have to. I haven't calibrated my test kits (I know, I know

).......
Tap water from a cup that sat out for about 24 hours:
NO3: 5 ppm
PO4: .5 ppm
pH: 8 ppm
gH: 357ppm (26*)
kH: 464 ppm (20*)
(I've always thought we had REALLY hard water)
Tank measurements 2 days out from a 50% water change (EI dosing on a 110 gal.)
NO3: 20 ppm
PO4: 5 ppm
pH: 7.2
gH: 107 ppm (6*)
kH: 438 ppm (24*)
CO2 from Chuck's calc: 45ppm