I'm pressed for time so this will be brief - I may be able to answer more fully later, but perhaps this will help.

A calcite filter has not pH control - as much as can dissolve in the time the water contacts the media, will dissolve, and the pH will rise accordingly. Particularly in relatively clean waters, it is likely that pH will be raised above 7.0, which is fine.

pH measure the amount of acid in your water, more specifically, free H+ ions. Alkalinity measure water ability to neutralize acid. Iron, and other metals, can form complexes that make pH control difficult.

I would suggest your install an iron filter. With the amount of iron in your water it would be ridiculous to do otherwise. Simply removing the iron may make your pH problem better, or it could make it worse, depending upon the form of your iron. Get the iron taken care of, then retest pH to see what you've got.

Thanks for the explanation. I had a Katalox filter installed last Friday, which seems to be doing a great job of taking out the iron. PH is off the charts at the moment (>8.5 which is as high as my test kit goes). The salesman did say this would happen, and that the PH would settle down in a month or two.

The calcite & softener are plumbed in after the katalox. Once the PH settles down, I was going to try to bypass these selectively to see how they affect the PH, hardness & alkalinity. Would it be okay to put these on bypass on a long-term basis if they're not needed?

Absolutely - if you do intend to bypass long term, you will want to ensure the softener is regenerated prior to bypass. The calcite bed will likely turn into a rock, so if you intend to bypass it long-term, empty it first.

I would bypass the calcite short-term right now - it's not needed at the moment anyway. Just watch your pH and run the through the calcite if it becomes necessary. If you don't end up needing the calcite, test your water hardness downstream from the Katalox to determine whether the softener is necessary or not. If you do need the calcite, test downstream from the calcite so the softener may be set up properly. You don't want to bypass some water around the softener - it would be a control nightmare, but some adjustment can be made so that the water will feel less slippery.

I'm not sure how accurate my test kit is (I couldn't get a reading on my raw water, but a 2012 lab test showed the hardness at 52 ppm). But in any event, I'm getting hardness levels of 90 ppm with just the katalox filter, 108 ppm with the katalox + calcite, and less than 18 ppm with the softener.

In terms of taste, any combination of filters that removes the iron tastes fine, but the combination of katalox + calcite (without the softener) tastes really great. It's as good as any water I've ever tasted.

Without the katalox, the softened water feels a bit slippery. With the katalox, it feels super slippery - so much so that you need to be careful not to slip in the bathtub. The salesman says that this is temporary and due to the high PH, but time will tell. In practical terms, soap lathers fine in both the softened and unsoftened water.

My wife doesn't like softened water and really hates the super slippery water that we have now. Meanwhile I prefer the softened water as it leaves my skin less dry and seems to help with some eczema that I have. I put the softener on bypass today and my wife says that her hair looks better than it has in years (I couldn't tell the difference). Meanwhile my skin feels itchier than ever after taking a shower in the unsoftened water.

I guess I need to wait until the PH from the katalox filter settles down, but I'm wondering if there's something I could do that would satisfy both me and my wife. There are drains/spigots in the pipes before and after the softener. What type of problem would I have if I connected them with a washing machine hose and tried to mix softened & unsoftened water?

It also wouldn't be overly difficult to run a cold water line with unsoftened water to the kitchen sink and the bathroom that my wife uses. This might improve the taste of our drinking water and increase the hardness of the water in my wife's shower. Would something like this be a possibility?

Your water's natural hardness is low enough that you might be able to do without a softener IF your pH is high enough with the iron removed.

Seriously, don't try to mix without flow meters and control - it will be a problem. Running unsoftened water to those places you want hard water is a much better option.

Check pH with the calcite bypassed and see what you've got.

Thanks. I'll re-test the PH once everything has settled down.

Running a separate unsoftened cold water line to my wife's bathroom would be feasible, but doing the same thing with hot water would be difficult (I'd have to get a second hot water heater). The hot water in that part of the house is pretty hot (close to 140 degrees), so a fair amount of cold water gets mixed in when taking a shower. Would doing something like this be a reasonable way to reduce the softness of the water in that bathroom?

Yes, that would work.

Thanks a lot for your help.