Reverse Osmosis Vs Carbon Filter (All You Need to Know)

The water that you get in your taps unfortunately may not be the safest water you can get. Not only is it highly chlorinated, but also filled with bacteria that are not visible to the naked eye.

Although your water regulatory body may even claim that it is up to the standards set by the government, it may still need a certain level of filtration in most cases.

Reverse Osmosis Vs Carbon Filter (All You Need to Know)

Reverse Osmosis Vs Carbon Filter

Reverse Osmosis Vs Carbon Filter – When it comes to filtration, there are different types of water filters out there. Due to the variety in the filtration systems and filters, it may make it difficult for you to pick one filter over the other.

Two of the most common water filtration systems include reverse osmosis and a carbon filter. But which one is the safest? Which one do you need?

To help you make up your mind and make an informed decision, here’s our take on reverse osmosis vs carbon filter. This article will allow you to learn how these filters work, how they can benefit you, and what are the drawbacks of each of the water filters.

See Also: Reverse Osmosis vs Distilled Water

Why Use A Filter At All?

Before we get into the filtration systems, you should first have an understanding of why you need a water filter. For starters, water filters essentially help you remove impurities, contaminations, disease-causing pathogens, and harmful bacteria from the water -thus making it safe for you and your family.

Based on where you live, your tap water may contain certain impurities in the form of dissolved particles. These include:

  • Aluminum
  • Calcium
  • Barium
  • Chlorine
  • Arsenic
  • Lead
  • Cadmium
  • Copper
  • Magnesium
  • Sulfate
  • Mercury
  • Nitrates
  • Radium
  • Synthetic Organic Compounds
  • Volatile Organic Compounds

These dissolved particles are filtered out by the water regulatory bodies to a certain extent. However, your water may still contain trace amounts of these particles and it may lead to both short-term and long-term health complications.

To cope with this, you need to have a water filtration system in your home. Not only will it help you remove these dissolved particles from your water, but it will also help improve the taste and odor of your tap water.

Related Article: Best Solid Block Carbon Filter

Reverse Osmosis: Overview

Reverse osmosis (RO Filters) is a water filtration system that passes the source water through a filtration media (semipermeable membrane) using high pressure. The filtration media filters out harmful contaminants and only allows the filtered water to pass through the body.

It filters out over 99% of the overall impurities and contaminations, thus leaving out clean and filtered water for you and your family.

Benefits and Drawbacks of Reverse Osmosis Water Filters:

The primary advantage of reverse osmosis is the fact that it removes a higher number of contaminations as compared to other water filtration systems. An RO system can efficiently filter out water up to a sub-micron level.

In fact, water filtered through an RO system is essentially regarded as the best water for drinking, and even cooking purposes.

Read More: Pros and Cons of Reverse Osmosis

what are the drawbacks?

During the filtration process of a reverse osmosis system, it also produces a significant amount of wastewater. Ideally, an RO system yields a ratio of 4 to 1 (wastewater to clean water ratio).

In layman’s terms, if you’re filtering out one gallon of water through a reverse osmosis system, it will produce a whopping 4 gallons of wastewater.

In addition to this, reverse osmosis systems are so efficient in terms of removing harmful impurities and contaminants that they end up removing healthy minerals as well. Calcium, potassium, magnesium, and other healthy minerals are filtered out. So, you will have to re-mineralize the filtered water.

Fortunately, there are certain filters that you can use in your reverse osmosis system that help you re-mineralize water within the RO system, so you do not have to worry about that.

Carbon Filters: Overview

Carbon filters are also referred to as carbon block filters. These filters use a special carbon obtained from natural sources like coconut shells and charcoal. The basic mechanism of carbon filters is to adsorb certain atoms, ions, and molecules from the water that flows through the carbon filter.

Keep in mind, the primary principle of carbon filters is adsorption and not absorption. Adsorption is simply referring to when these unwanted atoms, ions, and molecules stick to the surface of the filtration media, whereas clean water flows through the other end of the carbon filter.

Based on the phenomenon of adsorption, here are the impurities that are filtered through a carbon filter.

  • Chlorine
  • Mercury
  • Dioxin
  • Formaldehyde
  • Herbicides
  • Pesticides
  • Solvents

Primarily, there are two types of carbon filters.

These include:

Reverse Osmosis Vs Carbon Filter (All You Need to Know)

Activated Carbon

Activated carbon filters use an activated carbon media that is sourced from coal, coconut shells, and wood. These are one of the most common yet popular filters out there.

Catalytic Carbon

Catalytic carbon has the same physical characteristics as an activated carbon filter. But when it comes to removing chlorine and chloramines from tap water, it is highly effective due to the ability to process chemical reactions.

Benefits and Drawbacks of Carbon Filters:

Carbon filters are the go-to filters of many people due to the fact that they can easily be installed. In fact, they are also easy to use and maintain. Carbon filters can simply be set on your kitchen countertop and are way more cost-efficient compared to a reverse osmosis system.

Comparing the prices of reverse osmosis and carbon filters, carbon filters are over $150 cheaper compared to the simplest reverse osmosis system in the market.

The best quality carbon filters come at $50 tops. Seeing the prices, you may be able to guess the functionality and efficiency of both the reverse osmosis and carbon filters.

what are the drawbacks?

When it comes to removing heavy metals like iron, aluminum, or lead; and dissolved particles like sodium, magnesium, and other inorganic compound your carbon filter will have trouble removing these. In fact, carbon filters are also less efficient in terms of removing disease-causing bacteria and pathogens from water.

So, a carbon filter is only able to remove chlorine, mercury, herbicides, and certain solvents. But that’s it. For a heavy-duty filtration job, you will still have to use a reverse osmosis system, hence the price difference.

In addition to this, when it comes to the maintenance of carbon filters, you will also have to swap the filter more often compared to a reverse osmosis system. Since there is just a single filter involved unlike an RO system, it is exposed to more wear and tear and leads to the creation of small openings in the carbon filter.

The small openings are a result of the wear and tear over time, and it allows unfiltered water to simply pass through the water without getting filtered. It will then be mixed with filtered water which simply voids the purpose of using a water filtration system.

Reverse Osmosis Vs Carbon Filter: Which One Is Better?

To help you choose which filter is the best, here’s a simple comparison of the two.

Water Characteristics:Reverse OsmosisCarbon Filter
Bad TasteCompletely RemovesImproves
OdorCompletely RemovesImproves
TurbidityCompletely RemovesReduces
Organic CompoundsCompletely RemovesRemoves
Chlorine & THMsCompletely RemovesRemoves
BacteriaCompletely RemovesMight Control The Growth
VirusesCompletely RemovesMay Not Remove
CystsCompletely RemovesRemoves Some
ParasitesCompletely RemovesRemoves Up To Some Extent
ArsenicCompletely RemovesWill Not Remove
Heavy MetalsCompletely RemovesRemoves Up To Some Extent
Dissolved SolidsCompletely RemovesMay Not Remove
FluorideCompletely RemovesMay Not Remove

Frequently Asked Questions | Reverse Osmosis Vs Carbon Filter

How Often Should A Reverse Osmosis Filter Be Changed?

A reverse osmosis system comprises multiple filters, these include sediment pre-filters, activated carbon filters, an RO membrane, a carbon polishing filter, and a remineralization filter to add certain minerals to the filtered water.

Unfortunately, you will have to replace all of the above filters since they are exposed to wear and tear over time. But, with less frequency compared to carbon filters.

  • The sediment pre-filters in a reverse osmosis system allow you to remove contaminations like dirt, dust, and debris from the water. This is the first filter that your tap water would come across when you run it through the reverse osmosis system. Based on the usage, you will have to change the sediment pre-filter after every 6 – 12 months.
  • The activated carbon pre-filter in a reverse osmosis system allows you to remove chlorine and other harmful contaminants that lead to diseases. You will have to change it every 6 – 12 months depending on the intensity of your water usage.
  • Next is the RO membrane, you do not have to change it for at least 2 years. Yes, the RO membrane is the only component of a reverse osmosis system that lasts for more than a year. It effectively removes lead, pesticides and other carcinogenic substances from your tap water.
  • Lastly, the polishing or the post filter is what re-mineralizes your water. You will have to change it every year.

So, although reverse osmosis might come in a bit on the costlier side, it requires less maintenance compared to carbon filters.

How Often To Change Carbon Filters Reverse Osmosis System?

The life of your carbon filter varies depending on multiple factors, including:

  • The type of carbon that is used in your carbon filtration system.
  • The amount of carbon used in the filter itself
  • The intensity of usage

Additionally, it also depends on other factors like the shape of the filter; granular/block. Granular filters essentially have a bigger surface area. This is due to the fact that in a granular water filter, the carbon is split into smaller sections (granules). Whereas on the other hand, block filters simply comprise a compressed carbon block.

It is comparatively better in terms of removing contaminations from your tap water since the water has to pass through the much-saturated form of compressed carbon.

Similarly, the size and the quantity of the carbon in your carbon filter also help determine how often you need to change your water filter. Based on the size of your carbon filter, it will have a greater or a smaller number of pores. The greater the pores, the greater will be the lifespan of your filter.

So, collectively when all these factors are considered, you will have to change your entire carbon filter once or twice a year depending on your water usage.

When To Change Post-Carbon Filter Reverse Osmosis?

The post-carbon filter in your reverse osmosis system helps re-mineralize your filtered water. Ideally, you will have to change the post-carbon filter once a year to ensure you’re getting a good amount of minerals in your water.

See Also: How to Add Minerals to Water?

Reverse Osmosis Vs Carbon Filter

Summing Up which Is Better Reverse Osmosis Or Carbon Filter

Comparing the two, reverse osmosis system might come in a little on the costlier side but it is way more efficient in terms of removing bad taste, foul smell, turbidity, bacteria, disease causing pathogens, and other contaminations compared to a simple carbon filter.

In addition to this, a reverse osmosis system also requires lesser maintenance due to its longer lifespan so all in all, a reverse osmosis system will yield better results for you and your family.


This is my blog about the ways and solutions that can help you improve your health by taking more value from drinking water. As improving health means a lot to me, I decided to create the Water On Top project with the purpose to reveal the benefits of water, the finest products to take our daily water to another level, and much more great stuff about water that I believe is on top of our nutrition.

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