We have an Autotrol 255/440i control valve water softener and a whole house sediment filtration system. There's no brand label on the sediment housing, but it is blue and is 5" in diameter and 10" high. The company that installed the softener and WH filtration unit installed a 4 layer, 20 micron, 2.5" diameter x 10" high sediment filter cartridge. They also sold me 6 more of this type/size for use when the filter needed replacing. I didn't think anything about this at the time of installation, but now that we have been having hard water problems for several months (which we didn't during the first year or so of installation), I wonder if the filter is part of the problem.

My question: Will a 2.5" diameter WH sediment filter properly filter out sediment inside a 5" housing, or should I be using the large diameter cartridges instead?

FYI, we have always changed out our cartridges every 6 mos. They have been dirty but not excessively so. This last time, the cartridge was so dirty that it actually looked like it was made out of red clay dirt (the type of dirt we have here in Oklahoma). We are on well water with never a problem in the past, but have had a severe drought all summer long. So I am wondering if the excessive dirtiness is caused by a severe lowering in our area's aquifer or if the cartridge, because it is too small, is not providing proper filtration.

Thanks much in advance for your help. I am new to this forum and am not very technically oriented!