If you look back in history to where the early civilizations began, you’ll see that all of them started near a great river. That’s because water is one of the few elements that can sustain life. However, today’s generation doesn’t have the advantage of pure and clean water that the early civilizations had. This is the reason why many are looking at methods such as reverse osmosis and water filtration to provide them with safe drinking water.

Reverse Osmosis vs. Filtration has always been an argument that has torn many homeowners. If you’re facing a decision between these two methods, it’s important to note how each method works, and their advantages and disadvantages.

RO and filtration are actually very similar in terms of how they work. Both of these methods require filters to effectively remove the harmful particles in the water. A filter is essentially a semi-permeable membrane that allows substances to pass through based on the size of their molecules.

Water molecules are usually smaller than salts and bacteria; hence they are able to pass through the filter. However, there are chemicals and toxins that have molecules which are even smaller than water. For those types of contaminants, a special filter known as a carbon filter is needed. Carbon is effective in absorbing these contaminants, thus allowing only the water to pass through.

Reverse Osmosis

So where does the Reverse Osmosis vs. Filtration argument start? Well, in reverse osmosis, the system uses pressure to better filter the water. It’s very effective in keeping salts out of the water, which is the main reason why it’s often used onboard ships, or for fresh-water aquariums. Large-scale reverse osmosis filtration plants are even effective for cities in coastal regions.

The disadvantage in using reverse osmosis is that the system wastes a lot of water. For every gallon of pure water that it produces, the reverse osmosis system sends 2-4 gallons of water down the drain. Also, reverse osmosis systems can be destroyed by chlorine. So if your water is chlorinated, you have to use a special filter called a cellulose triacetate (CTA) membrane.

The reverse osmosis filter also has pores that are too small for essential minerals to pass through it. Your body needs a certain amount of minerals such as calcium and magnesium for it to be able to function properly. Unfortunately, reverse osmosis filters cannot accommodate the molecules of these minerals; hence they are filtered away with the toxins.


When you talk about filtration, no pressure is used to filter the water. For the water to achieve its “pure” state, it has to go through several filters before it can be consumed.

The advantage with filtration is that it doesn’t filter away the essential minerals that you need. However, filtration is at a disadvantage when it comes to speed. The fact that the water has to pass through several filters means that the process is tedious and slow-paced. It also means that you have to replace more filters than in the reverse osmosis system.

Another disadvantage of the simple filtration system is that, because it’s a free flowing system, the water may not have enough time to come in contact with the carbon filter. If this happens, it’s possible that the carbon will not be able to absorb all of the contaminants.

If you’re going to pick a side in the Reverse Osmosis vs. Filtration argument, considering the advantages and disadvantages of both systems is a good strategy. What’s important to note is filtered water is better than non-filtered water. So whatever system you go for is a good decision to make.