Do Reverse Osmosis Systems Really Work?

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While the industrial sector has long been aware of the effectiveness and low cost associated with reverse osmosis water purification, the process has been a bit slower on the consumer side.

Some people still question the effectiveness of reverse osmosis systems and the strong claims made about them.

So in today’s post, let’s address the question, do reverse osmosis systems really work?

Key Takeaways

  • Reverse osmosis and reverse osmosis systems do really work. They are extremely effective at removing close to all impurities from water.
  • The effectiveness of reverse osmosis and RO systems has often been tested and certified by independent third-party organizations like the EPA, CDC, NSF, WQA, and IAPMO.

Does Reverse Osmosis Really Work?

First of all, does reverse osmosis really work?

The short answer is: yes, reverse osmosis really does work, and it works just as well as it’s advertised – it removes practically all impurities from water, leaving you with almost pure H2O.

It’s not hard to verify this for yourself! All you need is a TDS meter, which you can buy at most hardware stores. Simply take one sample of unfiltered water and one sample of reverse osmosis water and compare their TDS Levels – you’ll see the difference with your own eyes. TDS stands for total dissolved solids and is a measure for all the dissolved solids combined in water. They make up a large part of the impurities/contaminants found in water (what they don’t include are suspended solids). Reverse osmosis reduces water TDS by up to 95% and more.

Alternatively, if you don’t want to spend money on a TDS meter, you can do a simple taste test. Even if you’ve been generally happy with the taste of your water so far, you’ll still likely notice an improvement once you take a sip of reverse osmosis water.

tds meter in glass of water

A third option would be to have a sample of your raw water analyzed in a lab and compare that to the amount of impurities found after the water has been processed by reverse osmosis.

It’s also worth remembering that reverse osmosis is not even a new thing in general. It’s been around for decades, and the only recent change is its growing popularity on the consumer market. Water treatment plant operators have been aware of the benefits of reverse osmosis for a long time, and it’s been recommended as a water treatment option by many organizations such as the EPA and the CDC.

How Reverse Osmosis Water Filtration Works

Reverse osmosis filtration relies on a simple process: Water is pushed against a membrane lined with fine pores at a high level of pressure. As a result, water molecules are able to pass through the pores of the filter, while all contaminants mixed with the water get ejected and sent away with the wastewater stream.

The only real downside of the process is that it can waste a lot of water – as many as 3-5 gallons get wasted for every single gallon of water that gets purified. But other than that, there are no real disadvantages to using reverse osmosis for purifying your water.

Do Reverse Osmosis Systems Really Work?

Do reverse osmosis systems really work? Yes, not only do reverse osmosis systems really work, but they actually regularly get evaluated and certified by different independent organizations, including the NSF, WQA, and IAPMO.

If you want some extra peace of mind about the performance and quality of the reverse osmosis system you’re buying, you should focus on models that have specifically been certified for their contaminant reduction rates, like the AquaTru Countertop RO system or the Aquasana OptimH2O.

The AquaTru has been specifically tested by the IAPMO and is certified for NSF/ANSI standards 41, 53, 58, 401, and P473, covering more than 80 water contaminants in total. These include fluoride, chlorine, chloramines, lead, arsenic, nitrates, and many others.

The OptimH2O by Aquasana is similarly impressive, covering NSF/ANSI standards 42 and 53, among others. It’s especially good against arsenic 5, chromium 6, and reduces cysts in the water by more than 99.6%.

What Does Reverse Osmosis Remove from Water?

Reverse osmosis removes most types of impurities from water, with some minor exceptions like dissolved gases. It’s a very effective method of water filtration, dealing with aluminum, ammonium, arsenic, iron, and much more. Here are some common examples of contaminants removed by reverse osmosis:

  • Aluminum: 98%
  • Arsenic: 96%
  • Chloride: 88%
  • Copper: 97%
  • Cyanide: 88%
  • Iron: 96%
  • Lead: 96%
  • Nickel: 97%
  • Sodium: 90%
  • Sulfate: 97%
  • Other dissolved solids
  • Radionuclides
  • Certain pesticides
  • Particulates
  • Bacteria, viruses, cysts
  • Asbestos

blue reverse osmosis membrane

Pros and Cons of RO

Here are some of the advantages and disadvantages of reverse osmosis:

Pro: Always Have Fresh, Clean Water

One of the main advantages of reverse osmosis is that it provides you with fresh, clean water on demand. You don’t have to worry about what you’re drinking and whether your water contains any contaminants, and you’ll be able to have the water supply for your entire household filtered if you want to.

Pro: Easy to Install and Maintain

It doesn’t take a lot of effort to install a reverse osmosis system, and maintaining it is not difficult either. You just have to remember to replace the filter elements on a regular basis.

Pro: Improve Your Hydration

By switching to reverse osmosis water, you can improve your hydration as you’ll feel more motivated to drink water on a regular basis. Some people note a significant difference in how they approach their own hydration after making the switch, so don’t be surprised if your habits change completely in this regard.

Con: Wastes a Lot of Water

One of the two main downsides of reverse osmosis is that a lot of water is wasted in the process. Typically, 3-5 gallons of water must get discarded for each gallon that gets purified. This might seem excessive, but keep in mind that the efficiency of reverse osmosis systems can be improved in various ways, while wastewater can also be reused.

Con: Removes Minerals

Water naturally contains various minerals which end up in your organism when you drink it. This is normally not a bad thing – quite the opposite, in fact, as those minerals are healthy in certain amounts. Reverse osmosis completely removes those minerals from your water, meaning that you’ll have to compensate for them in other ways. Thankfully, that’s not very difficult at all – various options exist, such as mineral drops or remineralization filters.

When to Use a Reverse Osmosis System

As we’ve learned, reverse osmosis is really powerful. It removes almost all impurities and contaminants from water. But there are other water treatment methods as well, and many are highly effective, too.

So when to use RO specifically? If you have more than one type of contamination in your water and levels are severe, reverse osmosis is probably our best bet (have your water tested!). However, if you water quality is quite decent already, reverse osmosis might be over the top and all you need might be a simple carbon filter or something similar.

If you have any thoughts about the question, does reverse osmosis really work, please don’t hesitate to leave a comment below!

About the Author Alexandra Uta

Alex is a content writer with an affinity for research and a methodical attention to detail. Since 2020, she has fully immersed herself into the home water treatment industry only to become an expert herself. Alex has been using water filters and similar products for years which has gained her lots of hands-on experience.
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