I have very much enjoyed where this thread went, as I don't often get to do a lot of looking at the small-scale products that are available for home systems. Operators at water plants tend to deal in pretty big numbers.
In a related story, the kid that plays fiddle with us (swear I'll quit calling him a kid when he turns 30...

) lives not far from me, and has roughly the same source water, very low pH, which of course means very high iron, manganese, sulphur... etc. Whoever built the house he bought put in some system I've never seen before that uses some liquid form of copper-sulfate to recharge the media, sort of like a manganese greensand filter uses potassium permanganate... anyway, I assume it's some kind of ion exchanger, but can't figure the thing out. This much I do know - it ain't workin'. Sharp, huh?

Iron is the stereotypical 'big one' in these parts... it's plentiful in the Earth's crust here, and soft, aggressive, low-pH water strips it (and other stuff) right out and into the water table. Luckily, iron is easily oxidized returning it to solid, (ferrous >>> ferric) and easier to remove. One time I designed a contraption that (woud have) made my well pump pump out of a diffuser into a series of plastic barrels. I pictured something like a couple shower nozzles, just anything to aerate the 'raw' water, then allow the iron to settle as it passed through the sedimentation barrels. Would have been a maintenance headache... but then again, they all are to a degree.