Without knowing more, I can pretty much assure you there are filters and other devices to do to your water whatever is needed. I can also assure you that you can pay a LOT of money for devices to do things that you don't need done. You can also pay LOT of money for devices that do NOT do what you need done. I would certainly recommend a water test before before going further. Really not that big a deal. However, if you want a quick indication without specific knowledge, some people get one of those pure-water pitchers that let the water trickle through an activated charcoal stack. Then they compare the taste of that water with their tap water. Sometimes they live with it for a week or two to be certain of their opinions or those of their friends. If you choose to do that and that taste is OK with you, your taste problem can be solved by a suitable-volume activated charcoal stack, probably under the sink with an extension over to the frig. ice-maker. They certainly do make whole-house versions if you want. Pretty much the same idea but bigger and more expensive. And the activated charcoal stack in either will have to be changed out from time-to-time. Some say they're "maintenance free".....but they're not. You'll have to pay attention. These units will NOT help with deposits on appliances. That's different. You're talking mineral residue there...probably from just hard water. Charcoal stacks do not soften water. Different issue entirely....and covered ad nauseam in previous threads. Use the search function.

Jenny, Any update on what you ended up doing? I installed a whole house softener for hard water issues, but I have odor issues (sulfur and chlorine mostly). I'm leaning toward adding a charcoal filter before the softener. We also have RO in the kitchen and wet bars. Also, you could always just have another hole drilled for the RO faucet without replacing the granite slab. If you have an undermounted sink, the new hole is all you need. What did you end up doing?

dunno about that. Look harder at EWS's site and you'll see they sell softeners, just the same as any other company that sells softeners. The hard (forgive the pun) truth is that if you have hard water, an ion exchange softener is the most practical and cost effective way for a homeowner to remove calcium from their water supply. What is hard water? 1-3 grains/gal is slightly hard water, anything over 20 grains is ludicrously hard water. Really, if your water is apt to make soap scum rings on your tub, spot your glasses and dishes and leave white powdery deposits on plumbing fixtures, your water is hard and you need a softener. Here is a link that might be useful: water softener

My suburb purchases its water from Chicago. The water is not considered hard and homes on Chicago water typically do not have a water softener. Over the years, the smell and taste of chlorine has gotten much stronger - either I'm getting more sensitive to it or more is being added to the water. I was using an under-the-sink filter with 2 cartridges and the single cartridge units that are placed ahead of the shower head. When I touched up my main bathroom 3 years ago, I decided to scrap all the separate filters and install a whole house filter. I purchased this one from Discount Filter Store: http://www.discountfilterstore.com/two-housing-filter-system-pentek-bbfs-22.html and two cartridges - one for sediment and one a carbon filter. So far, I've been totally happy with it. I did not notice any pressure drop and no more chlorine taste or smell when taking a shower. The cartridges are cylinders, 20" long and 4.5" in diameter. Together, I paid around $90 for the pair, last time I replaced them. When replacing them, you have to wash out the housing with a chlorine bleach solution and then install the new filters. Because of the size of the housing, that's something best done in a basement laundry tub. Then there's new o-rings and food grade silicone lubricant for the o-rings. Definitely not as easy as replacing the under-the-sink versions, but once installed, every faucet, shower and tub are covered. Unfortunately, also every toilet and sill cock (I didn't have the house re-plumbed). However, since my water usage is low, I only change the filters every 2 years - have only done so once; time to do so again is coming up. Since I have a meter, it's easy to know how much water is used vs. the rating of the filter. I had a plumber install the system for me. He put in a full complement of ball valves such that I can bypass the filters and still have water in the house. I also purchased the special wrench that fits into the grooves of the housing making it easier to remove.