Is Reverse Osmosis Better Than Filtered Water

If your curious mind has wandered off and started thinking whether reverse osmosis is better than filtered water, then you are in the right place.

While both systems are effective in reducing the number of contaminants in water, they each function in unique ways.

Discovering the differences between reverse osmosis and a water filter system will leave you with a better idea of which one is best for your needs.

It is true that both have advantages and disadvantages but it can be hard to decide which one is best.

Reverse osmosis and filtered water are very advantageous but in certain applications. However, as you read on, you may find that both types of systems have benefits that you want to use in your home’s water filtration. If this is the case, it may be best to invest in a system that combines both filtration methods.

To help you make up your mind, we are going to discuss the pros and cons of both filtration systems and find out the differences between the two. By the end of this article, you should have a clear idea on which system is better for your requirements.

Reverse Osmosis — What is it?

Reverse osmosis systems, otherwise known as “RO”, use reverse osmosis to reduce large numbers of contaminants in water. The way in which it works is fascinating. Firstly, it is important to understand what osmosis is.

Osmosis is a naturally occurring process that is of fundamental importance to our lives as well as all living creatures on earth. It is when a solvent moves through a membrane from a solution. This solution has a low concentration of solute to a solution and a high concentration of solute.

The fluid (solvent) that moves through the membrane during osmosis is typically water and the membrane has to be semi-permeable to allow molecules to pass through but stops others.

Solutes are dissolved substances found in the solution on both sides of a membrane. Osmosis continues to happen until each solution on either side of the membrane reaches an equilibrium state (becomes balanced).

As you can probably guess, reverse osmosis does the opposite and turns this process on its head. Here, a solution has a high concentration of solutes that are moved across a semi-permeable membrane. These are forced to a solution with a low concentration of solutes. In order to force a solvent across the membrane, a force from the outside needs to be greater than the osmotic pressure within.

RO systems begin with water that contains large numbers of contaminants. This water is forced through a semi-permeable membrane allowing the solvent to move through the membrane.

Other contaminants or solutes that are in the original solution don’t get passed through. When reaching the other side of the membrane, this is where the solution with fewer contaminants is and your water becomes filtered.

Filter Water — What is it?

There are a range of filter waters and all use some sort of filtration media to reduce contaminants in the water. One may not use the same filtration method as another but the most common type of filtration media in water filters is activated carbon.

This carbon is a unique type of charcoal that is treated with oxygen so the surface area of the carbon is increased. To put this into perspective, 1 gram of activated carbon tends to have a surface in excess of 32,000 feet. The surface area attracts and captures certain contaminants through an adsorption process.

In the adsorption process, the porous nature of the activated carbon means it has many small areas where contaminants become attracted to the carbon before becoming trapped there.

Reverse Osmosis vs Filter Water

So is reverse osmosis better than filtered water? Both systems are very effective at reducing the number of contaminants in water. The main difference is that they discard slightly different contaminants.

To fully understand which is the better choice, we need to see what contaminants are removed by each.


  • Salts and nitrates
  • Minimizes mineral content from hard water
  • Copper and lead (heavy metals)
  • Protozoa (Giardia and Cryptosporidium)
  • Organic compounds such as fluoride which is usually added to tap water
  • Bacteria such as Salmonella and E. coli
  • Viruses such as Norovirus, Rotavirus, and Hepatitis
  • Reduces the amount of arsenic

Reverse osmosis isn’t as effective when removing organic compounds like Toluene, Benzene, solvents as well as VOCs (volatile organic compounds).

These systems tend to produce a little wastewater through the filtration process. This carries the contaminants removed from the water away before being deposited.

Read on to see what water-filters remove.

Water Filter:

  • Various chemicals and VOCs. (Solvents, fuel oil, dioxins, polychlorinated biphenyls, and some radioactive materials)
  • Disinfectants such as chlorine which is used in treating water
  • Unpleasant tastes and odor in water
  • Possible to remove pesticides, herbicides, and certain organic contaminants

Activated carbon filters are outstanding when removing organic compounds. However, they are not as effective when reducing the number of other contaminants. These include calcium and magnesium, which are known to be the cause of hard water. Further contaminants include heavy metals such as lead, fluorine, microbes, and salts.

Some ways to help you decide which is the best situation system for you is to have your water tested and consider what you will use the water for most.

Testing your water will give you a good idea of what contaminants are present in your water. Understanding what is in your water will help you decide which filter can tackle those contaminants best.

How you plan on using your water filtration system can make it much easier to decide. If you just want filtered drinking water, consider having a reverse osmosis system installed underneath your sink faucet.

If you’re still unsure, maybe consider a combination of both. This way, you can use a pure water filter installed where tap water is needed into your house and a RO system to supply drinking water through your faucet.

In Summary

Is reverse osmosis better than filtered water? It can be difficult to weigh up the pros and cons of reverse osmosis and filtered water systems.

RO systems are wonderfully effective at reducing many contaminants including nitrates and salts, protozoa, viruses, bacteria, heavy metals, arsenic, and minerals.

On the other hand, filtered water systems are very good at reducing organic compounds and chemicals within the water, therefore reducing bad tastes and odors.

It is recommended to have your water tested to see what system will find your water’s contaminants best and guide you towards healthy, purified water every day of the year.