Does whole house reverse osmosis make sense?

The short answer is “YES” but that doesn’t mean that it is for everyone.  We will consider the pros and cons of a whole-house RO system and you can decide if it is for you or not.

First of all, water quality varies greatly from well water to surface water to municipal water.  Well water may have things like iron, sulfur, manganese and tannin which almost always have to be removed, especially in the case of a whole-house RO system.  Those contaminants must always be removed before the reverse osmosis process.  Let’s not forget that reverse osmosis removes the largest spectrum of contaminants at the most economical cost of any water treatment process.  Essentially, a whole house reverse osmosis system will remove 98 to 99% of most contaminants including Total Dissolved Solids (TDS), sodium, chloride, sulfate, nitrate, arsenic and a plethora of other chemical and organic contaminants.

One of the key ingredients to a whole house reverse osmosis system is proper per-treatment, which includes removing the iron, sulfur, manganese, tannin and other nuisance elements.  So, ahead of an RO system, it is essential that filtration or oxidation of these contaminants are accomplished.  If the water is hard, then it needs to be softened or (what I prefer) use an anti-scalant to prevent hard water build-up on the membranes.  Anti-scalant systems are gaining popularity because no water is wasted and no salt is needed.

A whole house RO system consists of the aforementioned pre-treatment, the reverse osmosis system itself, an atmospheric storage tank, a re-pressurization pump, ultraviolet light or Quantum Disinfection and sometimes a calcite filter to raise the pH or add some TDS back to the water.  Here is what a city water whole-house RO system might look like:



Who might need a whole house reverse osmosis system?  Lots of people.  It could be health related in that they may want to remove as many chemicals as possible from their water.  Many people have a sensitivity to such chemicals and therefore need a whole house RO system.  In other cases, it may be that there are contaminants in the water that create ascetic issues such as high chlorides, sodium, sulfates and others.

Sometimes we see water that has TDS levels in excess of 2,000 PPM (the USEPA recommends drinking water that is below 500 PPM).  I’ll grant you that the water you use to flush your toilet doesn’t have to be super clean, but the amount of water used for flushing toilets in very insignificant compared to most other uses for water in your home.  Washing dishes or clothes, bathing, shampooing, shaving and cleaning in clean reverse osmosis water is a pure joy.

Back in the day, people used to bathe in rainwater, which is generally absolutely soft.  When I was in Haiti a few years ago, we would wait for a heavy rainstorm and stand underneath a downspout plume just to enjoy a good shower.  With shorts on and a bar of soap, we enjoyed every second of that shower.

If taking a shower in the cleanest water on the planet, without chemicals, pesticides and hardness appeals to you, then maybe you are a candidate for a whole house reverse osmosis system.  If you want to be able to drink from any faucet in the home, then maybe a whole house RO system is for you.  Maybe you just want the best water possible.  If so, a home whole house reverse osmosis  system may just be what the doctor ordered!


This article has 93 Comments

  1. Mark – We live in a rural setting on 20 acres. Our well has good quantities but also has high levels of TDS, (1500), one of which is sodium @ 611 mg/L. Hardness is 150 and pH is 8.6. There is also a chloride level around 600 mg/L. Other measured factors are Calcium 59 mg/L; Iron 0.054 mg/L; Magnesium 0.18 mg/L; Silica 10.8 mg/L; Zinc 0.004; Fluoride 1.4 mg/L; Sulfate 160.0 mg/L; and, Turbidity of 0.1.

    We have been told that a R.O. system would solve the water quality problems and besides taste, corrosion is certainly one of the most aggravating problems with our water. We have replaced several plumbing fixtures in our house since building it in 2010 due to corrosion. I would hate to go to the expense of a whole house system only to find we had not solved the corrosion issue. As a side issue, we have plumbed the house for fire protection but have never yet allowed our well water to be introduced to the system for fear of corrosion ruining the fire sprinkler heads. This is another big reason we are considering a whole house R.O. system.

    There are only two people living here full time. My wife and I. We use less than 100 gallons a day, (around 70 – 80), but would like to size the system for a family of four should we decide to sell at some point. Can you help with some information regarding the issues I’ve mentioned? Thanks – Mike

  2. You guys need to fire your writers. I have a hard time taking you seriously when whoever wrote this copy doesn’t understand verb-subject agreement.

  3. Yes, I agree. We will get professional journalists to write… who know nothing about water. You will have an enjoyable reading experience but fixing your water may be a problem. Is that OK?

    Is form over function what you are seeking? I am the writer. I have a college education, but I admit I am not a journalist. I do have 45 years of water treatment experience and am one of the highest certified Master Water Specialists in the USA, but if you want a journalist to treat your water then that can be arranged. The problem is: I may not write that well but he knows nothing about water…

    I do recall verb-subject agreement, but does the journalist know about the role of the Langelier Saturation Index or competing contaminants in treating your water? Sometimes, you can’t have the whole package, but you might have to decide what is most important – Good Water or Good Grammar?

    Nobody has put out more water treatment content than me the past 15 years (by tenfold), so I apologize if I make a few mistakes in grammar. You get what you pay for and that’s the best water treatment experts in the USA (grammar aside). #noghostwriters

  4. Mark, I think it is very informative and who cares about grammar. If every 10th person knew about these systems and how to instal them properly this country would ve much healthier. But people are dumb enough to buy bottled water which may be even worse than toilet water.

  5. Hi Mark,
    I have 2 questions
    Is a water softener still needed with this RO System?
    What is the water pressure like? We already have low water pressure where we live. Wondering what a whole house RO system would do. Thanks for your time.

  6. Is a water softener still needed with this RO System?

    It depends upon the hardness level of your water.

    What is the water pressure like? We already have low water pressure where we live. Wondering what a whole house RO system would do.

    It increases your pressure as it is internally controlled.

  7. Hi Mark,
    How do you get rid of iron and sulfur in the water? We have well water with a water softener, but the water still smells and I still have that lovely orange stain in my toilets and showers/bathtubs.

    Been thinking that a RO for the whole house would take care of the problem, but from what you say in your article, that is not the case.

    How do we remedy the issue then?
    Thank you for your input.

  8. Hello, I have a 3900 sqft home in well. Could you tell me the system that I need. I mean the works to get the best of the best. Lolol

  9. I just reread the article and couldn’t find the mistakes the grammar cop mentioned. So that search was a waste of time. But as for the most important part, the content, it was worth rereading it.

  10. Hey Mark,

    I have been trying to get a better understanding of RO systems and how they operate and some real technical information on them but information is scarce to say the least. My current system is about 19 years old, but it is still working minus some quirks. The recent problem I have run into is my booster pump failed that is feeding two 2.5×40″ membranes. I believe this system is producing a lot more waste without the booster pump working which is causing my well to dry up. I have ordered an ac motor to replace it. (pump is just a 1/2 hp motor connected to a fin hosing) Another thing I would like to do is add a third membrane to my system. Would this produce more water and less waste if I had two membranes connected to the source water and the third membrane being fed off the two source membranes? I’m also thinking about changing the size tubing from 1/4″ to 3/8″. All of the membrane connections are being downsized. I am not sure how this would affect my pressure going in to the membranes though if it would cause a huge issue.

    No one around us knows RO systems or is willing to share information, everyone is asking me to spend 3500-4500 on a new system that they can just plug in.

    Our Water information:
    TDS – 1600+ PPM
    Chlorides – 390 PPM
    Flouride – 4.53 PPM
    Iron – 0.21 PPM
    pH – 8.7
    Hardness – 1 grain

    Current Filter system:
    75gallon pressure tank
    Carbon cartrige filter in big blue housing
    5um Sediment in big blue housing
    1um Sediment in big blue housing
    (2) 2.5×40″ RO membranes
    2 150 gallon storage tanks
    Chlorine Feeder to storage tanks
    25gallon pressure tank w/ booster pump
    Carbon filter w/ backwash
    Acid neutralizer

  11. Steven,

    I would need to know a lot more about your water, like Silica levels, Langalier Index, Cation and Anion breakdown before I could answer intelligently. Our newest systems operate at 80 psi and at up to 80% recovery, so they waste only 11 gallon per every 4 gallons made, but a detailed water test is vital:

    Whether you can add another membrane depends upon the water test, the pump and motor.

  12. We have a fairly new well which produces quite a bit of water, but with hard pumping the turbidity increases to very cloudy levels. A nearby well produces very little water at the same depth, but the water is clear. When the new well was bailed during drilling, there was some mud to start with, then very fine sand, then gravels. This bailing was typical all the way to 373′. There was a problem area at about 278′ where the formation collapsed twice. Welded steel casing had to be used from above the surface to the well bottom. Slotted pipe with 1/4″ slots was used from about 250′ to 373′ since much of that formation produced water. The slots are large, but even smaller slots would not stop the very small suspended particles. This area in the well (278′) seemed to be an ancient river bed with boulders, to very fine sand with silt and lots of water. At first use, the well water was slightly cloudy, but became more clear over time. Then, with heavy pumping for hours, the turbidity shot way up. The turbidity appears to be very fine particles of possibly clay, silt, and sand. The particles are so fine they stay in suspension and go right through a whole house sediment filter and right through a carbon filter. A backwashing filter was recommended, but I wonder if the suspended particles will pass right through that filter. Our thought was to only treat the water going to the house. Most of the water is used for trees and gardens. There are no close septic systems and no surface water. The static water level is 216′, with some artesian pressure since the first water was found over 240′ deep. What do you recommend to get rid of the particles in suspension? Water in this area of the desert does typically scale swamp coolers.

  13. We have a well which produces soft sulfur smelling water. Have heard that an injection pump for hydrogen peroxide. We think we want a reverse osmosis system. How do we go about knowing which system to get? Do you test water samples? Thanks for you assistance.

  14. We have a well on two acres and are outside of city limits. We just tested Chromium 6 and are at 19 ppb. We have a RO system at the sink for drinking but are concerned about bathing and dishwashing. A local company came out to quote us at around $30,000 for a whole property system with a large holding tank and a leach line. He said for every gallon we use, a gallon and a half is used to wash away the contaminants. Is there an alternative to this? something cheaper and just for the house use? Watering our plants and washing our cars with filtered water is expensive and unessesary.

  15. Mark
    Enjoyed reading your comments on RO. I’m currently in the market looking for a whole house RO system. The only system I’ve seen so far is the one manufactured by Kinetico. Can you comment on Kinetico and provide any alternative systems. I live in the Wilmington, NC area.

    Thank You


  16. Ted,

    Here are the US WAter American Revolution RO systems:

    Kinetico systems are sold through dealers who pay commissioned sales people 20-30% to sell them. We sell direct, and cut-out the middlemen and offer a system with a lot more features at a lower price:
    Stainless Steel Membrane Housings
    Stainless Steel RO Pumps
    Uses 40% to 50% Less Energy
    3-Year System Warranty
    #1 in Longevity
    Made in the USA
    Legendary Technical Support

  17. Hi Mark,
    We have Kinetico Reverse Osmosis under kitchen sink that feeds to our refridgerator and ice maker. We would like to install a separate under-the-counter ice maker. I have heard using a completely separate (2nd R/O system) would be best for the under counter ice maker. Or even using 2 tanks to increase volume for that ice maker. I dont know how all of it woukd be installed. Any thoughts you have on this please would be great. Thank you for your time and expertise. Best Regards, Don

  18. We are needing a whole home system. We have had our well tested last year and they said it is high in sodium and manganese. Do you have a test that you send out for us to send back in to be sure the one we had is correct?
    I can send you pics of the system that was in place before and the test we had done. Not sure if any of it still works or is any good. The house was a foreclosure and we don’t know anything about the system. From what I read about your company I think if you can figure out what we need.
    Any help you could give us would be greatly appreciated. We are currently hauling water and not using the well.

  19. Don,

    Many under-counter icemakers use a lot of water. I have seen some that use up to 80 GPD. First of all, you will need to find out EXACTLY what is the MOST water it can use in a 24-hour period. Then a remote-installed RO can have a dedicated line to that icemaker. This is information that is vital, but many manufacturers don’t like to tell you. Let me know what you find out…

  20. We need a complete system for our well the water is full of minerals very salty and close to the ocean can you give me a price on a good system large enough to look after the whole house thank you

  21. Hello Mark,
    I must agree, the grammar Nazi might be from a different English teaching country and therefore misled. I found no issues. I have a home in SW FL and last year spent about $6K for a system by Culligan. I purchased from them believing they were among the best. today I don’t have any faith in the system. I keep getting errors on the softener side control station. I have to continuously play with it to make it work. when it is in error water will not stop back washing and the water in the house is yellowed. I have opted not to purchase their over costly service plan as it appears they are only going to put in salt every other month and the cost for that is just ridiculous. Any suggestions for these last comments would be greatly appreciated. I’d love to take them to court at this point for selling us a POS system that by means of internet clearly has global issues. I am more pissed at myself for not being more thorough with my research prior to purchasing. I was thinking about whole house RO but I’m not sure if that is the way to go. Two of us live here but it is a 3br, 2ba home on a well. I am very skeptical about the water but have no idea what is in it. The salesman from culligan used a test on the counter here at home so I doubt he knows what he is talking about. What should we do at this point? What tests should we have done? Is a whole house RO system really what we need?

  22. Mark,
    Looking for guidance on protecting my family. We have a 6 year old boy, and live in Wilmington, NC. I’m sure you’ve heard about the contaminants that DuPont/Chemours has been dumping in the Cape Fear river for the last 37 years. If not, please take a stroll down Google alley and let me know your thoughts.

    We are very concerned about drinking water, but also bathing, washing dishes and even watering our vegetables which we were striving to keep organic. Now to find out our drinking water has been contaminated with Teflon related chemicals is extremely disheartening. I was thinking of starting small, but honestly I want to do whatever it takes. Thoughts?

  23. Randy,

    This is a question that has popped up a lot lately and I am in the process of writing a blog on the subject (due out in the next day or two). However, there is not a lot of research on this new contaminant. Our Pulsar System 4 in initial tests has shown it is capable of removing in excess of 50% of 1,4-Dioxane and Gen-X in drinking water. However, if it were me, I would add a Reverse Osmosis System for Drinking after that just to polish it off. Additionally, more and more families are opting for Whole House Reverse Osmosis.

  24. Mark,
    I live in a rural area and have a well. I am concerned about the large amount of waste water associated with a whole house RO unit. Can you install the RO unit at the well head? I already have storage tanks and house pressure pump. Can you plumb the waste water back into the well head in order to eliminate the waste? I assume the water in my well flows into and out of it and the extra TDS would flow out of the well thus avoiding concentrating the TDS in the well.

  25. I would not do that, because over time, you would really “concentrate” the dissolved solids. Depending upon you water supply, our Whole House RO Systems waste as little as 1 gallon of water for every 4 gallons made.

  26. Hello,

    My water just tested at 10.7 ppb for arsenic. I live in southeast Michigan where arse ic is a normal part of life. What are my options?

    Thanks so much

  27. Maredith,

    There are several options, but I would need to know a lot more about the other contaminants in you water before making a recommendation.

    Do you have a detailed water analysis?

  28. Mark,
    I know this is an older post, but it is valid to my situation and I have a question about whole house RO. We have decided that the municipal water currently provided requires additional whole house filtering, specifically to address poor performance of water using appliances such as the clothes washer etc. My concern is the waste water generated by the system. We currently use an average of 15K gallons per month on a municipal system that where we pay for every gallon, am I correct in stating that a whole house RO system will increase my monthly water usage to at least 30K gallons? If that is a true statement, then whole house RO, as much as I would enjoy it, would not be financially feasible. Can you recommend another system that will still reduce solids and contaminants but that is more economical to operate?

    We are a family of 6 in an 1800 square foot home. The house is a typical 4 bedroom 3.5 bath track home. We do use several thousand gallons for irrigation and I believe I could install the system downstream of the irrigation but I do not know the effect that would have on waste water usage.

    I appreciate your time.

  29. Ron,

    If you use 15,000 gallons of RO water a month, you would waste about 3,700 gallons with our low energy, high efficiency systems. That would increase you water used to less than 19,000 gallons and you could capture that waste and use it on your lawn. It would involve a tank or tanks and a re-pressurization pump. It’s very do-able. If you want to discuss this further, e-mail me at

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