Reverse Osmosis Vs. Water Softening: Do I Need Both?

I have a water softener. Do I need RO?

If you have a water softener in your home, you may feel pretty good about your water. But in fact, even after being processed by a water softener, impurities may remain in the water you drink and with which you wash foods and cook. Reverse osmosis can remove those impurities from your already-softened drinking water –including 98 percent of all sodium left in the water from the softening process. 

And that’s not all, here are three reasons why reverse osmosis and a water softener make a great combination.

Why Reverse Osmosis and Softening Work Well Together A Softener Protects an RO Unit:

Reverse osmosis membranes are fragile. Although there is usually a small sediment filter in front of the RO, reverse osmosis has a hard time removing or reducing calcium and magnesium–the minerals that make water hard. So by installing a water softener WITH an RO drinking water system, the water softener or conditioner will reduce the water hardness, thus acting as a protective barrier for the RO system keeping it from fouling and extending the life of the membranes.

2. Quality Water:

Many people who choose to install a home water softener system also elect to install an under-sink reverse osmosis system in the kitchen. Such a system can be installed to service the kitchen tap, the lines leading to a refrigerator-freezer, or both.  In other words, a reverse osmosis system goes a step further than your water softener, ensuring the water you drink is even purer. 
Historically, reverse osmosis technology was used to desalinate water from the ocean. Today, millions of homes enjoy high-quality drinking water thanks to small RO units installed in their kitchens. Perfect Combination for Outstanding Water in the Home

A softener and an R.O. system are a great combination because while the softener will give you soft water throughout the entire home by removing minerals that make your water hard, an RO system will give your household outstanding drinking water by removing most impurities (including hydrocarbons, sulfates, cadmium, pesticides and more).

3. Cost Savings: 

Most water softener owners have found that with the savings in energy costs, extension of appliance lifespan, and lower soap/shampoo/detergent usage–a water softener can pay for itself pretty quickly. And not to be outdone–RO system owners find they save money, too. After installing an RO system, they eliminate the cost of bottled water from the family budget (as RO costs pennies per gallon), not to mention that most families save money by buying fewer sugaring drinks after an RO unit has been installed).

Thus, a softener and RO are a great pair that will reduce your expenses, plus provide you with outstanding, quality water.

Considerations When Choosing a Reverse Osmosis System

If you already have a home water softener system, you should choose a reverse osmosis system that will not interfere in any way with that system, and that will not be compromised by the operation of your water softener system. Evaluate warranties that come with reverse osmosis systems to learn exactly what is covered and for how long. Find out how much sound the system makes to be sure noise won’t be a problem, and learn how simple or complex filter maintenance is. 

Benefits You’ll Enjoy With a Reverse Osmosis System

By using a reverse osmosis system in addition to your water softener, you’re giving your family the purest drinking water possible. Reverse osmosis removes a number of impurities that are commonly found in ordinary tap water–making your drinking water taste better. With a reverse osmosis system you can be confident you’re giving your family clean, purified water that is so vital to their health and development. 

To learn more about WaterTech’s RO PureMAX II Reverse Osmosis drinking water system or WaterTech’s Reionator water conditioner, talk to an authorized WaterTech dealer near you.

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  • Hi,

    Of course, I think a RO is essential, because a softener can only soften water but not remove contaminants in water. If your water is very hard, a softener is also needed. They cannot be replaced by each other.

    • Colette McCullough

      Absolutely. We agree that reverse osmosis and water softening are a great combination for extraordinary water.

  • I agree with this post -RO is essential for a healthy life.

    • A RO system removes everything, depleting the water of essential minerals needed to maintain good health. Sure we get some of these minerals and natural elements in food and other sources. However, some studies show they are most beneficial in life’s most important and natural liquid (h2o). Our body consists of primarily h2o. Thus, nutrients are most easily and efficiently absorbed by the body when contained or infused in h2o.

  • I installed a RO system and it works great. It is essential for healthy life. And I think I can protect my family.

  • Doesn’t RO remove the good minerals in water also? What does it do to the water PH?

  • richard parker

    At present I have an whole house iron filter, and a water softner system.
    My understanding is that the water softner system pours lots of salt into the drainage system. True/false? How will the RO system help that condition?
    I live in a 2500sqft house with two people. The largest water use is washing and hygene. I have a well which does emit iron and or rust.(the reason for the wh iron filter) This filter has to be serviced once or twice per year to change the medium.
    what would be your recommendation?

    • Colette McCullough

      If sized right, a water softener on a typical home will use about 10 lbs of salt per week during the regeneration process. Most of that salt is used to create a brine solution to flush and recharge the water softener. An RO system won’t help prevent the brine solution from going to drain, but will improve your overall water quality. A water softener helps protect the RO membrane from clogging and scale buildup. With well water there are so many variables that affect any recommendation due to specific customer and application needs. Therefore, I highly recommend working with a local water specialist to evaluate and recommend the appropriate systems for your application. You can see if there is an Authorized WaterTech dealer near you by entering your zip code HERE. Good luck.

  • I have a client that lives in a resort. The resort provides RO water to her house. She would like to soften the water with a whole house water softener. I’ve read your article above and you mention the RO system to be placed after the water softener. What happens if it’s the other way around? RO water and then a water softener. Would she obtain supreme water this way?

    • If you have high hardness (Calcium) in the water you will always want to put the softener in from of the RO system. The softener will remove the calcium and protect the RO unit. Because RO is such fine filtration, if there is no pre-filtration or softener in front of the RO unit, the RO membrane will clog up and exhaust very quickly. But if you’re saying that the resort has a massive RO system that filters ALL the water going to every unit, then she could still reduce hardness with a softener. But if the water there is hard, chances are the resort has water softening equipment in front of the RO.

    • If you put a softener after a RO you will be adding sodium to the water. A RO system removes both the calcium (hardness) and the sodium (salt) from the water. If the resort supplies RO water, no additional conditioning is necessary.

      • Isaac Linton, CWS I

        If your water sample shows that you have hardness, iron and sodium in your water, a softener needs to go in front of the RO system to remove the Calcium and Iron from the water. Otherwise the Calcium and Iron will quickly exhaust the RO Membrane. A softener will add trace amounts of sodium to the water which negligible. The greater concern is high levels of sodium coming from your feed water source. The RO system is intended to remove that sodium. RO filtration is the finest filtration available.

  • If the GPG of your water is over 3, a softener is needed. A ro system is also needed to purify your water. The softener is just used to soften your water but not to purify it. And such a softener is also helpful to protect the membrane or your RO system.

  • Are we taking about whole house reverse osmosis systems after the water softener? This would eliminate the need for a carbon filter?

    • Colette McCullough

      Hi Brandi, in this post, we’re talking about a whole-house water softener and point-of-use RO unit (installed at the kitchen tap). RO units generally incorporate a carbon filter in the final filtration stage of the RO system. Does that answer your question?

  • If I purchase a hybrid water softener, do I need a reverse osmosis system also?

    • Colette McCullough

      Hi Diana, we don’t manufacture a “hybrid” system so can’t really say much about their capabilities. Perhaps call the company that makes the hybrid unit you’re considering and ask if RO is still a good idea. And we hope you’ll consider the Reionator, too. It goes far beyond just water softening in making your water taste and feel great. Of course, adding RO with the Reionator will take your drinking water to an even higher level…but the Reionator by itself can actually produce some pretty fantastic water.

  • How often you need to back wash the system ! I still smell rotten egg when taking a shower, how to remedy this situation ?

  • I have a R/O system and a softener. I am experiencing some sort of build up in the kitchen faucet that has the R/O system on it. Also something pink came out of it. I had another R/O system on this before and one day I turned it off and a clear white goup what hanging at the end of my faucet. It was thick and I called my water company and they had no idea of what it was and I was stuck with having to replace it. At this time the build up kinda hangs inside the end of the new facet and just flaps around when the water goes on. WD comes over do their maintenance check and still no answer. Help if you can.

    • Colette McCullough

      Hi Angela: If your own local water treatment professional can’t figure out the problem, then we’re stumped. Have you asked the local professional to test your water? Whether you’re on well or municipal water, the constituents in your water can change over time. Knowing what exactly is in your water can give a professional clues as to solve your water treatment issues. Hopefully, whomever you’ve hired knows more than system maintenance but also has a clear understanding of water chemistry.

  • I have a two stage whole house water filter system using 2 in. by 10in. Filtering down to 5 microns each. After that is a G.E. water softner. Istill am getting a white salt like deposit on all my faucets. I tested the water with hard water test strips. Getting a very hard results. Any idea as to what is the problem.

  • We have a town wide RO system just installed. Just wondering if I need to keep our water softener? Some people are saying yes and some are saying no.

    • Isaac Linton, CWS I

      Hi Julia: We definitely think RO and a water softener make a great combination. A softener can actually protect an RO system and extend the life of the system.

  • hi i have water softener in my home and i am going to install RO system but i am very confuse about which water i have to use for input in RO system ? from water softener or from city hard water ? i am living in area where city supply bore water so it’s very hard water can you please advice me thanks

    • Isaac Linton, CWS I

      Your RO system and a water softener make a great combination. By installing a water softener WITH an RO drinking water system, the water softener or conditioner will reduce the water hardness, thus acting as a protective barrier for the RO system keeping it from fouling and extending the life of the membranes.

  • When testing water hardness.. is it possible that the RO removes SOME of the hardness due to the filtration of the elements? either as a false positive or an actual effect of softening?
    We feel that our softener is failing but the hardness post softener is HARDER than post RO.
    Our membranes are being destroyed in very short order.

    I am confused as to the softened water POST RO. And am being told RO units can NOT soften water but am seeing the results that we are testing.

    The softener does come before our RO in the sequence btw.

    • Isaac Linton, CWS I

      Hi Brian: RO is extremely fine filtration and will essentially take out everything, that is why you are seeing hardness reduction post RO. I’d recommend getting your softener checked out asap to figure out why it’s not softening and also to protect the RO. It’s good that your softener in front of the RO to remove the calcium (hardness), iron, etc. otherwise it will exhaust your membrane very fast.

  • What would be estimated cost of a RO system to treat all the water used in a 4500sqft house, and would the water come out as “soft” from a West Texas hard water well supply, or would water softening in front of the RO still be required? We want to treat all the water in a new home being constructed.

    If water softening is required, what size system should be used, and what would be monthly cost of the salt and any other related equipment, filters, etc.?

    • Isaac Linton, CWS I

      Hi Bert: we hope you were able to reach our authorized dealership in the area for pricing. Thanks for contacting WaterTech.

  • Before we had our whole house water softener system installed, we used to drink straight from the tap. Now the water tastes terrible to me and I have to buy bottled water. Would an RO system improve the taste?

  • If I have a water softener do I have to have an RO or would an under the sink filter such as the 3m 3MFF100 work in conjunction to make good drinking water also?

  • Great reading, For living in this world, there is no alternative of water for the body to save a life. Water is a must to run the body. Water aids to run the body properly and helps to do all the functions well. Water is very essential for the cleansing system. Now the medical association has found that the body needs water to maintain the normal function of the body. Our body is made of mostly 70% of water. If we analyze the amount of water in our body we find that in blood the amount is 80%, in the brain, this is 75% and our main filter named liver is 96% water. You badly need to choose the best reverse osmosis system to fulfill the requirement of lives.

  • My RO system installed in 2007 is fine in producing “pure water” HOWEVER over the last 18 months i have monitored water usage and this has doubled compared to the previous 18months. The system flushes and that water goes directly to the drains. Water costs have increased greatly over the past few years so this is of concern. Could the system need replacing or can I adjust the frequency of flushing? The system is serviced (at a current cost £88 every 6 months).

    • Isaac Linton, CWS I

      Over time, chlorine in the water can eat holes into the RO membrane. As such, you will notice your system will be producing more water as it is flowing through the holes in the membrane. This will impair the performance of the membrane and system. You need to change out your filters every 6-12 months and the membrane every 1-2 years.

  • You mentioned that many people who choose to install a home water softener system also elect to install an under-sink reverse osmosis system in the kitchen. My brother and his family just moved into their new home and the water tastes kind of different. Do most contractors prefer homes to have both kinds of systems? Finding a water treatment specialist to come and help them might be a good idea.