What Does a Reverse Osmosis System Remove

Reverse Osmosis systems can remove many different contaminants

What Contaminants Do RO Filters Remove?

For decades, Reverse Osmosis water filtration has proven to be unrivaled when it comes to removing impurities from water in an efficient and cost-effective manner. Because Reverse Osmosis can effectively remove a wide range of impurities (such as asbestos, "forever chemicals" like PFOS, sulfates, cadmium, chlorine and lead) RO technology is becoming increasing popular.

During the multi-stage filtration process of an RO system, water will pass through pre-filters to remove sediment, large particles and chlorine, then on to a semi permeable RO membrane, which can remove most impurities down to .001 microns. Finally, water goes through a post filter which is usually a carbon filter to improve your water's taste.

athlete drinking water

5 Contaminants Reverse Osmosis Filtration Can Remove

Number 1

RO Can Remove Lead from Water
Household water pressure forces water through a series of RO filters. During this process, up to 98% of lead can be removed with a reverse osmosis drinking water system. Removing lead from drinking water has become increasingly important, as excessive lead levels have been found in the water of more than 22 million U.S. residents. Learn more about how to remove lead from drinking water.

Number 2

RO Can Remove Pesticide from Water
Reverse osmosis filter systems are generally able to remove 97-99% of pesticides, herbicides and insecticides from drinking water. The carbon block filters in the RO system can trap these chemicals.

Number 3

RO Can Remove Chlorine from Water
The carbon filters in a reverse osmosis water filtration system can remove up to 98% of chlorine from water. Many people want to remove chlorine from drinking water to improve water's taste and smell. The chlorination process at your local water treatment plant often leaves drinking water smelling like bleach. In the RO process, chlorine is captured by the Granular Activated Carbon (GAC) "polishing" filter designed to improve taste.

Number 4

RO Can Remove Fluoride from Water
Because of the many health concerns associated with the fluoride in drinking water, many households are looking for a way to remove it. Reverse osmosis filtration can successfully remove 85-92% of fluoride in drinking water. In the RO water filtration process, water passes through a semipermeable membrane, carbon filter and sediment filter to capture a wide array of contaminants. Learn more about the reverse osmosis process.

Number 4

RO Can Remove PFOS and Other Forever Chemicals from Water
Reverse osmosis (RO) is known to be effective in removing perfluorooctane sulfonate (PFOS) and other per- and polyfluoroalkyl substances (PFAS), commonly referred to as "forever chemicals," from water. RO is a water purification process that uses a semipermeable membrane to remove a wide range of contaminants, including ions, particles, and organic substances.

The semipermeable membrane in an RO system allows water molecules to pass through while blocking the passage of many contaminants, including PFOS and other PFAS. This makes RO a suitable technology for reducing the concentration of these persistent chemicals in drinking water and other water sources.

of contaminants. Learn more about the reverse osmosis process.

Top-Selling Reverse Osmosis Drinking Water Systems

Microline TFC-400-ESP RO System 50 GPD TFC-400-ESP

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AXEON Solo I All-In-One 4-Stage 50 GPD RO System (211470)

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GRO 1:1 RO High Efficiency 75 GPD Drinking Water System (GRO-75GPD)

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  • Proven, High-Quality System
  • Compact, Space-Saving Design
  • Eco-Friendly System Conserves Water
  • Designer Chrome Faucet
  • Standard Chrome Faucet
  • Designer Chrome Faucet
  • High-Flow 3/8" Tubing to Faucet
  • High-Flow 3/8" Tubing to Faucet
  • High-Flow 3/8" Tubing to Faucet
  • 4-Stages of Filtration
  • 4-Stages of Filtration
  • 4-Stages of Filtration
  • Compact 3.2 Gallon Storage Tank
  • Standard 4.4 Gallon Storage Tank
  • Standard 4.4 Gallon Storage Tank
  • Airgap and Non-Airgap Faucet Connection
  • Airgap Faucet Connection
  • Non-Airgap Faucet Connection
  • 50 Gallons Per Day
  • 50 Gallons Per Day
  • 75 Gallons Per Day
  • Made in USA
  • Designed in USA, Made in China
  • Made in USA
  • Free Shipping
  • Free Shipping
  • Free Shipping

How Much of a Contaminant Can Reverse Osmosis Remove?

Reverse osmosis (RO) systems can remove common contaminants from water including lead, nitrates, pesticides, sulfates, fluoride, Arsenic V pharmaceuticals, and much more.

The chart below demonstrates to what level the RO system will successfully remove or reject impurities (typically down to .001 microns).

For example, if fluoride is your main concern, you see that an RO system will eliminate up to 92% of it from your water. This is a partial list, and RO filtration can address many more contaminants than what is included here.

Typical rejection characteristics of reverse osmosis membrane elements and the contaminant percentage RO filtration systems will remove are as follows:

Protect your family with RO filtered drinking water

Amount of Each Impurity an RO System Can Remove

Fluoride (85-92%)
Lead (95-98%)
Chlorine (98%)
Pesticides (up to 99%)
• Nitrates (60-75%)
• Sulfate (96-98%)
• Calcium (94-98%)
• Phosphate (96-98%)
• Arsenic V (92-96%)
• Nickel (96-98%)
• Mercury (95-98%)
• Sodium (85-94%)
• Barium (95-98%)
• Potassium (85-95%)
• Iron (94-98%)
• Zinc (95-98%)
Forever Chemicals like PFOS (90-99%)
• Magnesium (94-98%)
• Cadmium (95-98%)
• Cyanide(85-92%)

What contaminants can RO filtration remove?

Reverse Osmosis Frequently Asked Questions

Can Reverse Osmosis Remove Bacteria?

Reverse Osmosis technology is not designed to remove bacteria and viruses. If bacteria enters the RO system, it can continually grow in pre-filters and deteriorate the membrane over time. Thus, most RO system manufacturers specify that the system "must be used with biologically safe water". Bacteria and virus removal is best achieved with a UV water sterilizer system. We highly recommend pairing a whole-house UV water sterilizer system (installed at your home's water point of entry), with a Reverse Osmosis drinking water system installed under the kitchen sink.

What Contaminants are Not Removed by Reverse Osmosis?

Reverse Osmosis systems do not effectively remove most bacterial microorganisms (such as viruses and bacteria), organic compounds, dissolved gases like methane, radon, and carbon dioxide.

Is RO Filtered Water Bad For You?

RO filtered water is good for you. Many chemicals and compounds that could potentially be toxic to your body are removed by reverse osmosis filtration.

Does Reverse Osmosis Remove Healthy Minerals?

While much has been said about removing minerals from drinking water, the reality is that our diets provide us with more than enough milerals for our bodies. The health benefits of removing Arsenic V, sulfates, pesticides, PFOS, and dozens of other contaminants far outweigh the concern of less mineral content in water. With a good diet, your body will have all the minerals it needs.

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