What are you trying to remove from the water? That will determine the appropriate filtration. What about your water is objectionable or worrisome? Taste? Odor? Metals? Bacteria? Color? Hardness? Sediment?

We have a reverse osmosis system with a water chiller and heater. Gerry from cleanwaterstore.com spent a lot of time on the phone with me helping determine what our requirements were and what we were trying to do and we decided that the reverse osmosis system with easily changed out filters was best for our needs.

It's been in a couple of weeks now and everyone loves it. It filters all our drinking water and you can taste the difference even with the hot water in coffee.

I put Watts Premier 5 stage reverse osmosis filters in my new house -- not just in the kitchen, but also in two of the bathrooms. They're sold at Costco for about $135 (cheaper than they are on Watts' web site), and the resulting water tastes wonderful. Our water normally tastes terrible, and I'm at the end of the run down from the mountain so was really concerned. But this water tastes great!

Here is a link that might be useful: The Watts unit I bought

Living here in the mountains of New Mexico, everyone is on wells and almost everyone I know has an R/O (reverse osmosis) for their drinking water. We have the Watts from Costco, also.
Pluses: they filter out the sediment and the bad tasting minerals. The water looks and tastes great.
Minuses: all R/O's take up a lot of room in the under the sink cabs; You have to change the filters every so many months (depends on how bad your water is). Word to the wise: think about how much the replacement filters will be and the ease in getting then (local store vs online) before choosing your R/O.
We don't have an alternative really, so with our new kitchen reno we're putting in a bigger cabinet (our plumber is so happy!). R/O's are a bit hard (awkward) to work on, especially in under-the-sink cabs with the wood strip down the middle between the two doors. Whatever you do, stay away from a cab like that if you can when opting for an R/O.

Another minus, from what I read, is that you waste 3-4 gallons of water for every gallon that is purified with a reverse osmosis filter. Expensive and wasteful, I fear.

Thanks for all the advice.

You are right to ask my goals, Alice. I of course was trying to take a short cut on this decision. I know we have lead pipes in our old building so i want to remove lead. What else? I don't know. I want the water to taste good.
Amazing how much one learns in this process. I just finished the research on counter tops (and selected soapstone) and was hoping someone just told me what to do with the water filtration! I'll call Gerry from Cleanwater and see if he'll spoon feed me the information...

sagni - I have no advice to offer since I too am at the beginning of this process, but I will say that "research" appears to be an absolutely endless requirement for the process! I am more or less permanently online researching and/or at the computer designing at the moment - I think I'm really GLAD I go back to work in 2 weeks since it will give me something else to obsess about for a while :)

Btw, I too am planning on adding an under sink filter so if you find out anything particularly useful could you post back for posterity? Thanks :)

We used to use a reverse osmosis undersink system. But it is really wasteful, and unnecessary for most municipal water systems.

Be aware that RO water should NOT be used in certain appliances or situations. Read your manuals to be sure!

We switched to the GE SmartWater double-filter system. Works well, inexpensive, any standard filter can be used for replacement. It's wonderful not to have to buy bottled water! It's probably saved us a lot of $$ over the last 17 years.

This has also been one of my research areas lately. There's just so many of them with a kitchen project!

The first thing any good water place should ask is whether you've had your water tested and ask for a copy of the results. How can they recommend something without knowing what needs to be filtered? Also, PH is really important with most water filtering systems.

The main issues that I was trying to solve were green scaling around the faucet heads and brown/rust staining in toilets. We only run our hot water through a softener, so anywhere that the cold water touched, our off-the-charts hardness showed build-up. We were certain that we had a lot of iron, but all tests have read zero for iron. ??? I thought the green around the faucets was due to copper leaching into our water. Tests showed zero for that too. It turns out the brown/rust must be from dirt/clay, so we added a whole-house iron filter that catches dirt, turbidity and lots of other things. Without a proper water test, we wouldn't have known what our real problems were. We're also adding a RO in the kitchen for the fridge and drinking.

I bought my stuff at budgetwater.com. The guys there are really helpful. In fact, one of the guys was on the phone until 9pm with my installer and called me back on Saturday when we had a problem. I'd highly recommend them.

We like our multipure. Expensive, but filters out everything you want filtered, leaves what you want left, and lasts a long time.

We have had a Multipure for years but the damn canister takes up so much room and I find the filter a pain to change, so we are looking for something easier to work with under the sink.
Granted, it does take everything out that you want out - but there must be others that do the same thing and are less cumbersome. And do you have to have a separate faucet or can you just filter the water that comes out of your regular faucet?

We put in a Watts (Costco) system. The one that we have is Zero Waste which is important for us on the left coast. It takes up some space, but we planned on it. Now there are no bottles about & I have yet to empty the tank which I think is 3 gallons. By the way, it is not hard to install. One side note, the faucets from Watts are fairly ugly, so add in a faucet upgrade, also not hard to do, but it will add a few dollars to the total. Hope that helps.

I would need a separate faucet for the filtered water. Plumbing modifications in Pre-war co-ops are tricky, requiring board approval..Interesting idea about having our water tested. Mayor Bloomberg speaking to the press a couple of years ago said the lead in our city water (from the old pipes) wasn't a big deal--we just have to let the water run 2 minutes before using it! That's when (with small children at home) I started having Bottled Water delivered. Thanks for everyone's thoughtful advice.

We actually find the multipure filter pretty easy to change. It does take up some space, but since we have two sinks, under-sink space is plentiful. We do have a separate faucet for the filtered water. Unless you buy one of the special faucets with built-n filters (KWC has one), I think that's the only way to do under-sink.

A "water filter" consists of two parts: 1) A housing that holds one or more filter cartriges, and 2) Those filter cartriges.

It is, of course, the filter cartridge that does all the work; the housing is just there to hold the cartrige(s) and to have something to connect the plumbing to.

There are generally two kinds of housing/filter arrangements you can buy:

1. Proprietary designs, which are designed to hold only their proprietary fiter design. Generally, there is only one type of filter available, or a small handful of types.

2. Industry-standard filter housings, and cartridges that are designed to fit these housings. There are at least dozens, and probably hundreds, of different kinds of filter cartridges available that fit in these generic housings, tailored for every imaginable need.

Proprietary systems are moderately expensive to very, very expensive, and give you very little flexibility. Standard systems are quite inexpensive, and give you enormous flexibility.

Standard-format filters are used in huge quantities in restaurant soda fountains, in filtered water dispensers at your grocery store, to manufacture bottled water like "Aquafina", in pharmaceutical companies, industrial processes, and many, many other uses. There are vast economies of scale here.

I am aware of no advantages whatsoever for the proprietary systems, except that they generate higher profits for their makers.

I have attached a link to a page of standard filter housings. I have essentially the #160196 housing (the dual housing about half way down the page), which I currently fill with a CGAC-10 chloramine filter cartridge followed by a CCBC-10 coconut activated charcoal taste filter. It does a great job for our water (SF Bay area Hetch Hetchy water, which is disinfected with chloramine).

Here is a link that might be useful: Water Filters Online

basnjas, re your comment >>We're also adding a RO in the kitchen for the fridge and drinking. Are you sure about your fridge? I was under the impression that most mfgs advise against using RO water for the fridge. Just wondering, that's all.

Sagni, I got ambitious, and went looking for a cartridge designed for lead removal. I found one!

Here is a link that might be useful: Lead reduction cartridge

RE: wasted water

I have an analysis report for the WHER25, done by Pace Labs. They say: the 4-1 waste only occurs with systems that DO NOT feature a storage tank or if the tank is bypassed (dumb). The WHER25 features a storage tank.

Is anyone familiar with Aquasana? They look good on paper, but their analyis is incompatible with the WHER25 report.

Feel welcome to respond direct to my e-mail.

Ok. I decided to just throw money at the issue. I am a bit overwhelmed with choices that need to be made this week--wallpaper, lighting, faucet....
so I went with the Doutlon Ultracarb. My reasons...it takes out the lead, filters are easy to change..they had some great faucets. Here is what I picked.
http://doultonusa.com/HTML%20pages/ip100SC.htm With this cool facuet: http://doultonusa.com/doulton_water_filters/Luxury-filter-faucets.php#mt800

I let you know in 6-8 weeks how it works! Thanks everyone for your input.

It is my understanding that the only way to remove fluoride is with RO. Is this correct?

We would like to have RO with both hot and cold water out of the same faucet. Will the InstaHot we already have work on the same faucet with the RO system? Anyone have this setup? We are considering Multi-Pure as they meet the NSF/ANSI 58 Standard.

Are we heading in the right/wrong direction? Any opinions, warnings, or advice?

Thank you, Deb

Sagni - looking for an update on how your filter is working.
Deb - The Multipure is good and that's what we have, so I am tempted to keep it even though it is a pain in the butt to change the filter and it is bulky. It is all very confusing and I have to make a decision soon. I think a lot of the brands meet the NSF standard - check the blurb on the Doulton site.

sagni, any update on the Doulton...I am considering them too due to the choice of faucets. Appreciate any feedback.

To add an update of my own since this thread has reappeared...

I can't speak to the chemical analysis of it, but I CAN say that we are delighted with our boring-common-or-garden-variety GE 2-stagem undercounter filter from HD. It was $99 (actually, I got mine for $69 because they screwed up and offered it to me at the price of the single-stage unit since it was their mistake), and the water tastes like... well, like WATER. It's great. No complaints at all (except possibly that the included faucet turns away from you if you mount it on the left side of the spigot, but it's not a big deal once you get used to it).

We got RO unit from Lowes - it comes with a white tank. It worked fine for a while- loved the water, but then it started to taste bad. So we replaced the filter, but the bad taste only reduced (although considerably). I did some reading and found that the bladder inside the tank can cause an off taste.
When we reconnect our plumbing I am not going to reconnect the RO. Will be looking for something else. I am currently looking at something called everpure.