Andy,
Yes, iron/sulphur unit appears to be working ok but I have not re-tested to see the exact iron level. I notice no sulphur smell. Unit is the same as the softener, AutoTrol 255 with the 8x44 tank. I do not know what the media is in the tank.
Let's round up to five grains hardness and there are only two water users.
PH is 7.6. I have no numbers on total dissolved solids.
My biggest concern was if the .75 cf tank could actually hold 1.0cf which is what they claimed. I have no idea why they configured the system that way but will ask next time I talk to them. The company is a water quality only company and has been in business for many years. They have both commercial and residential customers so I suspect (?) the know something about water softeners.
Earnie