How Reverse Osmosis Works

Reverse Osmosis provides clean delicious drinking water

What is Reverse Osmosis?

Reverse osmosis (RO) is a water filtration method commonly used to treat drinking water. RO has become popular due to its effectiveness in removing a wide variety of contaminants from water. This filtration type is also very economical as most RO water filtration systems cost about $350.

Although the term "reverse osmosis" sounds complex, the methodology is quite simple. In this article, we'll explain how the reverse osmosis process works, and what components are used in a typical under-sink RO drinking water system.

How an RO Membrane Filter Works

RO filtration works from pushing water through membrane Most RO drinking water systems are installed under the kitchen sink and incorporate carbon block, sediment and granulated activated carbon (GAC) filters. Although these types of filters are incorporated into a reverse osmosis filtartion system, they are also used in a variety of water treatment processes and applications.

The real "heart" of a reverse osmosis system is the RO membrane. The membrane works by utilizing household water pressure to force tap water through a semi-permeable membrane.

As the water is pushed through the membrane, the clean water is sent to a holding tank through one tube, and the contaminants are separated out flushed away down another tube.

Most RO drinking water systems are installed under the kitchen sink and incorporate carbon block, sediment and granulated activated carbon (GAC) filters. Although these types of filters are incorporated into a reverse osmosis filtartion system, they are also used in a variety of water treatment processes and applications.

The real "heart" of a reverse osmosis system is the RO membrane. The membrane works by utilizing household water pressure to force tap water through a semi-permeable membrane.

As the water is pushed through the membrane, the clean water is sent to a holding tank through one tube, and the contaminants are separated out flushed away down another tube.

RO filtration works from pushing water through membrane

What are the Stages of a Reverse Osmosis System?

At first glance, an RO system might look complex with all of it's tubes, housings, fittings, tank, etc. But the system is actually quite simpe. A reverse osmosis filtration system generally has 3, 4 or 5 stages.

All reverse osmosis systems will include an RO membrane, but the number of pre/post filters can vary between systems. Below we define the stages of a typical RO unit.

SEDIMENT FILTER
Sediment, silt, and dirt are filtered out in this RO prefilter. This is especially important because sediment can damage the delicate reverse osmosis membranes.

CARBON FILTER
Next, water enters the carbon filter. This filter has the ability to remove various contaminants that affect the performance and life of the RO membrane

REVERSE OSMOSIS MEMBRANE
The RO membrane is the "heart" of the RO system. This is where water is pushed through a semi-permeable membrane allowing purified water through to a storage tank, but holding back contaminants that are flushed away.

POLISHING FILTER
In a four-stage RO System, a final carbon filter (or post filter) will “polish” off the water to improve the water's taste and odor.

Because the reverse osmosis method filters water through these stages slowly, water is sent to a holding tank. This way, you have plenty to use when you need it.

What to Consider Before Purchasing an RO System?

As you select an RO drinking water unit, you'll find that systems and models vary in three basic ways:

1. Amount of water the system can filter each day. For example, a "50 GPD" system means it should be able to produce 50 gallons of filtered water per day
2. Number of filtration stages
3. Quality of components

Also, before purchasing a system, you may want to consider the cost of replacement filters. Some makes/models have very expensive replacement filters.

To help customers save money, we bundle high-quality replacement filters together in one simple kit. While these filters are not "brand name" filters, they're top-of-the-line filters gauranteed to produce the same high-quality drinking water you'd expect from OEM filters.

With some models, only expensive OEM filters can be used. In this case, many of our customers have converted their existing RO system with a new "manifold unit" to hold the filters, but kept their same tank and faucet.

interactive quiz to select correct RO filter system

Why Choose Reverse Osmosis?

If you're searching for a water filtration system that will give you outstanding water. Here area few reasons to consider RO:

Improves Taste
RO filtration improves taste, odor and appearance of water by removing contaminants that cause taste and odor problems.

Saves Money
With an RO system, you can cancel your water delivery service and stop purchasing cases of bottled water. Reverse Osmosis filtration provides “better-than-bottled water” quality water for just pennies per gallon.

Check out the Reverse Osmosis Buyer's Guide.

Simple Maintenance
RO systems have very few moving or replaceable parts make RO systems easy to clean and service.

Removes Impurities
Reverse osmosis systems can remove common pollutants from water including nitrates, lead pesticides, sulfates, fluoride, bacteria, pharmaceuticals, arsenic and much more. An Reverse Osmosis systems’ carbon filter will also remove chlorine and chloramines.

Find Out Why Milions OF Households Have Reverse Osmosis Drinking Water Systems

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Top-Selling Reverse Osmosis Drinking Water Systems


Sold out	Sold out	Sold out
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

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