Filtration Technology

Different Types of Reverse Osmosis Systems

5 min read

Are you unknowingly poisoning yourself with dangerous contaminants like lead or arsenic?

If you don’t filter your water, you could be drinking these every day right out of your tap!

Luckily, reverse osmosis (RO) filters can kick those toxins to Timbuktu.

But not all RO systems are equal…

Here’s what you need to know about the different types of RO systems so that you can choose the best one for you and your family:


Countertop filters are self-contained systems that sit on a countertop and are perfect for tiny places where a bigger under-sink system won’t fit.

Under sink RO systems are easy to use once installed. All you have to do is turn on the faucet!

Tankless RO systems are the next generation of RO filters. These modern systems can filter water so quickly that they don’t even need a storage tank.

The average American family spends $400 a year on bottled water. RO systems can save you about $300 a year.

Benefits of Reverse Osmosis Systems 

Here are four BIG benefits of using RO:

1. Improves Taste

By eliminating pollutants that cause taste and odor issues, RO filters enhance your water's flavor, smell and appearance.

2. Saves Money

You can cancel your water delivery service and stop buying bottled water if you have a RO system. Reverse osmosis filtration provides better-than-bottled water quality for less money.

3. Simple Maintenance

RO systems are easy and convenient to maintain. 

4. Removes Impurities

It's no secret that RO systems can remove up to 99.9% of all unwanted chemicals and yuckies from your water. 


Some people believe that RO filtered water is so pure that it can damage the body's mucous membranes due to lack of minerals. The good news is you can always get an RO filter with remineralization so this is never an issue.

What Is Reverse Osmosis Filtration?

Reverse osmosis removes hard minerals, heavy metals, and up to 99.9% of hazardous pollutants.

It works by pushing water through a very fine, semi-permeable RO membrane, which eliminates the majority of the toxins by trapping them on the other side.

With that said, the RO membrane is just one of several stages in an RO system. 

Let’s take a closer look at these different stages of filtration in action:

Stages of a Reverse Osmosis System

Some RO systems include all of these stages, some leave one or two out. 

In general, though, higher quality RO systems include all of the below stages of filtration:

Step 1: Sediment pre-filter to remove dust, dirt, rust and debris

Step 2: Activated carbon filter to remove chlorine, heavy metals, and improve the taste and smell of the water

Step 3: Reverse osmosis membrane to remove 99.9% of remaining contaminants

Step 4: Activated carbon post filter to catch any remaining pollutants

Step 5: Remineralization filter to add healthy amounts of electrolytes like magnesium and calcium back into the water. 

RO filters help reduce plastic waste by significantly cutting down on the amount of plastic water bottles families use every year.

Different Types of Reverse Osmosis Systems Saves Plastic Water Bottles

Countertop vs. Under-sink Systems 

Now you can have the same high-tech water filtration technology in your home that big companies use to make high quality drinking water. 

Of course, you can always go all-out and spend thousands of dollars to install a whole-house RO system — that way every inch of plumbing, faucets and appliances will be protected. 

But what if you just want clean drinking water and that’s it?

In that case, you can choose between a lovely countertop or under-sink RO system. 

Let’s take a closer look at these two most common types of RO systems:

1. Countertop RO Systems

As the name implies, countertop systems are free-standing systems that sit on a countertop (or the ground). 

They are best for small spaces where there isn’t room for a larger under-sink system.

Most are so small that you don’t have to give up too much kitchen counter space or worry about a complex installation process.


  • Compact size 
  • Simple installation
  • Easy maintenance  
  • Can pack it up and take it with you


  • Takes longer to filter water
  • Uses up counter space

2. Under-sink RO Systems

Under-sink filters are by far the most common type of RO system. 

Once installed, they’re effortless to use because all you have to do is turn on the faucet.

However, installation can be a tad tricky, so it’s always best to have it installed by a plumber. 


  • Most efficient way to remove 99.9% of contaminants
  • Easy to use
  • Can filter plenty of water
  • Easy to maintain


  • Harder to install 
  • Produces more water waste that other systems 

What’s Better, an RO System with a Tank or Without a Tank?

Some RO systems include a tank for clean water storage — others do not. 

So which is the best option for your home, tank or no tank?

To make the decision easier, we broke down the pros and cons of each:

RO Filter with Tank

After the filtration process, drinking water is stored in a hermetically sealed tank so it’s ready to go whenever you need it. 

These are great if you’re out in the country or want the peace of mind of having a lot of extra water on deck. 

Early in the evolution of the water filtration systems, storage tanks were standard because the filters were too slow to purify enough water on demand. 


  • If the water supply is turned off temporarily, water in the reverse osmosis tank can get you through that period
  • Convenient to get water fast


  • Requires a larger space for installation and storage
  • Water that’s stored in the tank for long periods may taste "off"

Tankless RO Filter

Tankless RO systems are the most recent evolution of RO filtration. 

Modern systems are able to filter water so fast that there really isn’t much need for a storage tank. 


  • Some people believe that tankless RO water tastes fresher because the water doesn’t sit around in storage
  • Produces less wastewater than other RO systems
  • Saves money on your water bill
  • Filter water on-demand in seconds whenever you wish
  • Takes up less space (no gigantic tank to store) 


  • Costs moret to buy than an RO water filter with a tank
  • Requires more electricity to function
  • Due to the lack of a storage tank, this system cannot store water that may be retrieved in an emergency

With Remineralization vs. Without Remineralization

Did you know that natural mineral water contains major micronutrients like magnesium, calcium, and trace minerals?

Unfortunately, RO filtration removes these minerals that are essential to health. 

The good news is that some RO filters include a final remineralization stage to add healthy minerals back into the water. 

Here are some other advantages of drinking remineralized water:

  • You’ll get a calcium boost to strengthen the bones and teeth. 
  • Extra magnesium to calm the nervous system and relieve anxiety. 
  • Some RO systems remineralize with sodium and potassium too, which support the muscular and nervous systems.
  • Water that contains electrolyte minerals helps you quench your thirst faster.
  • Better taste
  • Ideal for cooking and preparing tea or coffee. In fact, a lot of restaurants swear by RO water for this reason. 

When was the last time you tested your tap water?

With all the dangerous chemicals lurking in local water supplies, it’s important to test your water at least once a year. Check out your community's most recent test results by entering your zip code into the box below.

Is a Reverse Osmosis System Right for You?

RO systems are one of the most practical and effective solutions for providing safe, delicious water for you and your family. 

Under-sink systems cost only a few hundred dollars and can keep up with the drinking water demands of most families. 

Aside from the above average wastewater that they produce, there aren’t a whole lot of downsides to RO filtration. 

Just make sure your RO system includes remineralization so you get those healthy minerals! 

All Cloud Filters include remineralization. 

They also use built-in software to monitor water quality for pollutants 24/7, and you can check the results in real time through the app on your phone. 
Click here to learn more.


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