Looking for the best RO water purifier? A reverse osmosis system offers health benefits and purified drinking water for your home. Unlike some of the other water filtration systems out there, RO systems are able to remove most, if not all, of the contaminants hanging out in your drinking water. Most RO filters are rated 99% effective against petrol chemicals, chlorine, traces of lead, and many other chemicals harmful to your health.
Reverse Osmosis Filter Buyer’s Guide
Are you new to water filtration systems? We have been looking at the best RO water purifier models on the market. The reverse osmosis (RO) water filter system is one of the best to buy due to its effectiveness at removing contaminants. You can easily install most of these systems underneath your kitchen faucet.
There are several things that homeowners should look at when trying to find the best RO water purifier. Here is a detailed guide on how RO works, what to look for, and all of the health benefits you’ll receive from installing one in your home.
What is Reverse Osmosis System Filtration?
Reverse osmosis refers to a water purification system that allows water to pass through a membrane that removes most contaminants. While other water filtering systems simply use mesh, heat, or active carbon, reverse osmosis is actually able to remove smaller microbes and particles.
Ions, molecules, and bacteria are no match against reverse osmosis systems. It can also remove nitrates and nitrites.
How Does Reverse Osmosis Work
Osmosis is a natural process where a weaker saline solution can move towards a stronger formula. So, if you have two containers that are connected, but there is a membrane in between, then the container with fresh water will move naturally towards the saline container.
However, in reverse osmosis uses a pump or some type of force to move water through the membrane, which captures molecules, micro-organizations, bacteria, and other particles.
Is the Reverse Osmosis Water System the Top Water Purifier?
While several factors may contribute to what is considered the “top” choice, reverse osmosis filters typically get out the most contaminants because they use a longer, multi-stage filtration process. With many other systems, you only get a two to three stage process that involves active carbon filters.
However, RO companies create multiple stages for water to pass through before it is stored in the tank. Water will need to pass through multiple carbon filters, as well as a membrane that catches all of the microscopic chemicals left over from the first few stages.
One thing that does happen with even the best water purifier is that your pH levels can become problematic if there is too much acidity. RO systems are known for their acidity levels since they remove much of the minerals. With the remineralization stage, you’re able to get a balanced, alkaline water level that won’t hurt your stomach.
What Do Reverse Osmosis Filters Do?
Typically, an osmosis filtration system will also have multiple stages in the cleansing process. This means that the membrane captures most contaminants, but it will likely go through multiple filters, resulting in desalinated and demineralized water. This is because water molecules are allowed to move through the membrane, while contaminants are not.
Typically, an RO water purifier can remove 99% of contaminants. These are collected by the filters. Only RO filters with cross filtration systems can remove them completely from the membrane.
In the first stage, sediment is removed as well as other larger contaminants like stones, rust, and silt. Then, the carbon filter is the next step, straining out harmful but smaller particles, such as chlorine. The next step is a carbon filter, where the remaining water is suspended and removes microscopic particles. After going through multiple filters, the water passes through a membrane that removes any other contaminants.
Most water purifier brands provide a step-by-step look at how their reverse osmosis works and what filters are needed.
Health Benefits of a Reverse Osmosis Water Filtration System
With RO technology, you’ll have fewer contaminants in your water, but what does that mean? Well, in every glass of tap water, there could be hundreds of contaminants and chemicals. While in small doses, these may not cause any harm, some chemicals can lead to severe diseases and health problems.
The special membrane in RO water filters helps to remove these contaminants, leading to the most purified water that you can drink. Here are some the benefits of RO purified water.
The CDC has studied RO water filters and found that they can remove trace amounts of lead, making it more safe for consumption. With the buildup of lead in the body, sufferers may exhibit problems with fertility, muscle damage, nerve damage, and higher blood pressure. In large quantities, children may suffer even more as lead can cause brain damage and anemia.
Better for Cancer Patients
When you have cancer, you don’t want any contaminants going in your body. This requires many patients to drink purified water. The best way to do that is to install a reverse osmosis purifier. With chemotherapy, cancer patients have a severely weakened immune system. With untreated water used for drinking or cooking, cancer patients may get an infection with water that hasn’t been properly cleaned.
The CDC also did a report on Cryptosporidium, which is a parasite that was discovered in contaminated water samples. Once the parasite reaches the small intestines, it can cause diarrhea, fever, and stomach cramps. RO can remove this parasite and many other microorganisms from drinking water.
Helps with High Blood Pressure & Liver Disease
You can remove salt from your water using reverse osmosis as well. The CDC reported that larger sodium molecules can be found in water, but these are removed during the purification process. If you have any type of kidney disease, liver disease, or high blood pressure, you likely have strict sodium limits.
What is Removed by Reverse Osmosis Filtration
While there are many filters on the market, reverse osmosis was able to remove or reduce most of the contaminants found in today’s drinking water supply. There are some common tap water contaminants that active carbon filters aren’t able to reduce at all, unlike RO filtration.
Here is a complete list of contaminants removed and reduced by the reverse osmosis filtration process:
- Nitric acid
For a complete list of all chemicals removed by reverse osmosis filtration, check out this list.
Why Get an RO Water Filter?
Reverse osmosis creates the purest drinking and cooking water for your home. They are typically set up in the kitchen, but you can use them in the bathroom as well. These systems usually have multiple stages for cleaning water, including a single pass or multi-stage filtration with carbon activated filters.
The efficiency of an RO system depends on the strength of its multi-stage process. With multiple filters, you are likely to get 99% clean water. However, all filters are rated based on TDS, which means total dissolved solids.
TDS refers to inorganic components to your water, such as potassium, chlorides, sulfates, bicarbonates, sodium, and so forth. While this is typically measured in a lab, it’s clear that most drinking water supplies have a few contaminants, ranging from chlorine to microorganisms.
If you are looking to have the cleanest drinking water, then reverse osmosis systems are recommended. You may find that a system has a higher rating or is certified with an NSF seal. This means that the filter has been found to remove lead and major contaminants from the water.
How Reverse Osmosis Filtration Works
Osmosis systems typically have four to five stages of filtration. This means that they have a casing that must contain multiple cartridges and membranes. If you don’t have the cabinet space underneath your sink, you may need to find another way to install some of these systems, as they can be quite bulky. However, if you are determined to have pure drinking water, then RO is your best bet.
Here is a step-by-step look at how these systems filter out contaminants:
Step 1: This is the sediment and large particle removal stage. Basically, anything that’s floating in your water will be removed during this process. These are larger chemicals and solids, such as rust, stones, silt, and clay. Typically a reverse osmosis filtration system will have a five-micron cartridge at this stage to start the filtering process.
Step 2: At this stage, you will likely find an active carbon filter. This removes many of the unseen but harmful chemicals in your water, such as fluoride and chlorine. This is also where your water’s taste will change, removing that chemical metallic taste.
Optional Step: Here you may find another carbon filter to pick up anything that was missed in the previous stage.
Step 3: Water moves through the RO membrane. This is a semi-permeable material that can remove microscopic particles from the water. It’s made to remove molecules that are bigger than 0.0001 microns. Radioactive and invisible heavy metals are typically removed at this stage, as well as trace amounts of lead.
Step 4: This is the final filter and will try to remove any lingering odors or chemicals from the water.
Optional: Remineralization is a key part to the taste of your water. While RO does remove most contaminants, it also removes good minerals as well. This process puts back the pH and good minerals so you can have clean-tasting, healthy water.
Videos About Reverse Osmosis
RO Water vs. Bottled Water
Most people are now aware that bottled water is not healthy for many reasons. If it’s spring water, it can be damaging to the environment, but it’s also about drinking water that has been stored in plastic bottles. Many studies have proven that plastic may contain harmful BPA chemicals, which can be attributed to cancer risks.
However, RO water filters provide water directly from your faucet. You don’t have to worry about the effects of plastic or environmental problems, as long as you purchase a filter that has a high water efficiency.
Reverse Osmosis vs. Carbon Filters
There are a variety of water purification processes out there. Reverse osmosis is definitely the most successful at removing every kind of contaminant. While there is still a slight percentage of negligence, it’s safe to say that RO filters typically remove 99.99% of all contaminants. However, you don’t get the same rate with a traditional active carbon filter cartridge.
In fact, most RO water filters have a multi-stage purification process, where the water moves through multiple carbon filters and membranes, allowing you to get the cleanest water possible. With active carbon filters, you may actually need to replace the filters more, and you’re not preventing things like lead and arsenic from getting into your water.
Features of Top Reverse Osmosis Filtration Systems
Most reverse osmosis processes work the same way. They all use a semi-permeable membrane that catches most of the contaminants remaining after a vigorous multi-stage process. However, some of the lower-rated and single-process RO filters are listed under reverse osmosis filtration systems, but they don’t really have a multi-stage process or a very strong membrane. They may not be able to achieve the same efficiency as other RO filters.
These are some of the features that we look for in high-quality RO filtration systems:
You definitely want a reverse osmosis filter that uses multiple carbon filters in addition to a membrane. Typically these stages go up to 7 or more, and they involve multiple active carbon cartridges, membranes, and mesh filters. The first carbon stage removes chlorine and other chemicals before they even reach the first membrane. The next part removes any dissolved organic or inorganic material, removing almost everything that is bigger than a water molecule alone.
However, there may be multiple carbon filters before the membrane process. There could also be a remineralization stage where purified water is adjusted to balance the pH, which leads to better drinking water overall. RO water tends to have high acidity after going through the cleaning process.
Type of RO Membranes
There are two types of reverse osmosis membranes that you find with these systems. These are known as:
- Thin Film Composite (TFC)
- Cellulose Triacetate (CTA)
Both of these are able to filter out contaminants, but CTA membrane is able to get more chlorine out of the water. However, it needs to be replaced faster due to catching so much bacteria. The process for using a TFC membrane is a little different, as chlorine has to be removed before it reaches the membrane through active carbon filters instead.
While osmosis systems with a permeate pump are a bit more expensive, they reduce water waste by 80% and increase water production significantly as well. It can also fill the storage water tank faster. This is a non-electric pump that uses the movement of the waste water to pump faster.
Easy to Install
It’s always important to check out the installation instructions on any reverse osmosis system. Typically, these are installed below the kitchen sink. They may need to be mounted on your cabinet’s wall or hook up to your water line. If you don’t have plumbing experience, it could be difficult to install without a simple process and instructions. If you look at the instructions, you’ll find that many reverse osmosis filtration systems have just a few steps and don’t require you to install secondary spout.
With secondary spouts, you always have drinking water readily available, but you’ll need to find a way to cut through your countertops to place the spout next to your kitchen sink. It’s important to look at the installation kit beforehand and read reviews so you know if it will be difficult.
One thing to keep in mind is the PSI of your water pressure at home. These systems typically need a water pressure of 40 to 100 psi. You can read these specifications before you purchase to get an idea of what’s best for your home.
High Rating and Certifications
In the description of the filter, you’ll find ratings and certifications that show how well the filter works to reduce and remove contaminants. If it has received an NSF certification, it can remove 99% of all chemicals. However, some certifications are only for specific chemicals or materials, such as lead.
RO filtration is rated by how much clean water it can produce each day in gallons per day or GPD. This means that if you have a highly rated system, it likely can produce clean water very fast, which is more convenient.
Reverse Osmosis Water Filter FAQs
Is it safe to drink reverse osmosis water without remineralization?
There are some cases where reverse osmosis water filters can actually cause problems. One woman had issues with gout after switching to reverse osmosis that had high acidity. While not all reverse osmosis filtration systems have this issue, you may need to buy a calcium carbonate filter if your filtration system doesn’t include one.
Does reverse osmosis remove fluoride?
In the United States, water municipalities began adding fluoride in trace amounts starting in 1945 to the drinking supply. However, this caused problems with areas that had too much groundwater, leading to an abundance of fluoride. Reverse osmosis is able to remove fluoride from your water, as well as many other types of contaminants that can cause distaste, discolor, and disease.
The University of Nebraska found that reverse osmosis removes all kinds of impurities from water, including fluoride ions. This includes dissolved particles like magnesium and calcium, as well as pesticides.
Does an RO water filter system need to be installed?
This depends on the type of water filtration hookup you want. If you want to have your osmosis water filter hooked directly into your water faucet, then you’ll need to attach water lines to the filtration system and place it under the sink. Many systems come with an instructional guide to help you install it so that you don’t make any mistakes.
One thing that you’ll need to know is the PSI (pounds per square inch) that your kitchen faucet is rated for. You may need to purchase a pressure gauge that measures in PSI to know what your house is rated for. Most homes are between 40 and 80 PSI, which is fine for most reverse osmosis systems unless specified otherwise.
Is reverse osmosis better than other water filters?
For water purification, there are about three popular ways to filter out contaminants, including:
Active carbon filters
Out of these three ways, reverse osmosis is well known for getting almost everything out of your water. This includes contaminants and healthy minerals, however. Distillers don’t do a great job of getting out volatile chemicals such as chloramines. Active carbon can’t remove lead that well.
Reverse osmosis is the only system that can truly provide pure water that is 99% free of all contaminants. It’s the reason why so many cancer patients use that system because it results in water that won’t hurt their weak immune systems.
How often do you change the filters in an RO water system?
With long-lasting filter capacities, you may be able to wait over a year before changing out the carbon filters. However, many of these filters are only rated to last six months. These typically cost between $30 and $70 depending on the brand and size.
The reverse osmosis membranes need to be replaced every two to three years. These are typically found in most hardware and home appliance stores, or you can find deals on them by shopping online.
Best Reverse Osmosis Water Filter Reviews
Ready to buy the best reverse osmosis water filter? These are some of the top-notch water filters available currently. We rated these systems based on the ability to produce purified drinking water that tasted great and tested negative for most contaminants.
The iSpring water filter brand is well known for its highly-rated systems. The iSpring Reverse Osmosis Alkaline Remineralization filter offers an incredible system that can produce 75 gallons of purified water per day. Water goes through six stages of filtration, which has earned this system an NSF gold seal.
In fact, iSpring can remove over 1,000 contaminants, including 99% of all lead traces. Since RO filters can produce highly acidic water, the iSpring system has a remineralization phase that produces balanced, more alkaline levels of water. While we wish that you could control this, as with some systems, the real goal here is to produce the highest quality of clean water. The iSpring system does just that.
- Raises pH and improves taste
- Water leakage alarm included
- Removes up to 99% of lead, and 98% of all chemicals, sediment, and heavy metals
- Includes 4-gallon water storage tank
- NSF WQA gold seal
- Only has average water waste efficiency, typically losing 3 gallons of water per 1 gallon of purified water
- Filter capacity is a bit short
- Does not have any UV features
The APEC Five Stage system is incredibly popular and has a very high rating, which is why we decided to review this system to see how well it actually removed chemicals from our drinking water. This system uses a five-stage process that is rated for 50 GPD. We found that the water tasted great and removed 99% of contaminants, including trace amounts of lead, chlorine, fluoride, and petrol chemicals.
You will need to replace the filters for stages 1, 2, and 3 after the six-month mark. Replacing filters in this system is a bit of pain, but it’s not unlike many of the older RO models. We loved that APEC includes a TDS meter so that you can check the contaminants in your water. Unfortunately, this RO filter doesn’t have a remineralization phase to make the water more alkaline.
- RO membrane life up to 3 years
- 4-gallon water storage tank
- Includes one-year limited warranty
- Removes 99% of contaminants
- Filters need to be replaced every six months
- Higher water waste
- No remineralization stage to get a better balance of acidity
The Express Water Reverse Osmosis Filtration System has a five-stage purification process that comes with a large tank and beautiful spout. It also includes four replacement filters and is rated for 50 GPD. We really liked how easy it was to install this system just by following the instructions. We also found that it removed 99.99% of all contaminants, including chlorine, fluoride, nitrates, calcium, arsenic, bacteria, and lead.
However, the system itself takes up a large space under the cabinet. You will likely have to reserve half of your cabinet space under the sink for your Express Water system. However, it does have one of the largest water storage tanks and a high rate of water efficiency, meaning that you’ll get the most water back from your RO process.
- Removes almost all contaminants, rated for 99.99% removal
- Removes 108 major contaminants
- NSF and ANSI 68 certified
- Includes one-year limited warranty
- Incredibly water efficient
- Quite bulky in design and takes up a large amount of space
We were eager to test out the Brondell RO Circle Water Saving Filtration System because of its water-saving smart technology that claims to be 10 times more efficient than other reverse osmosis filtration systems on the market. However, it’s the design and easy installation that truly was impressive. Brondell has created a sleek package that holds all of the filters for the multi-stage RO process in a high-end looking case.
It’s also been rated with a WQA seal. While it only has a four-stage filtration process, it also received certifications for NSF and ANSI Stds. This means that it can filter out almost all contaminants, including lead. We also liked that this system focused on reducing water waste and has a rapid refill rate. The designer faucet included was also quite stylish and fit our kitchen’s look nicely.
- Highly efficient
- NSF, WQA and Ansi rated
- Four-stage RO process
- Incredibly sleek design that saves space
- No remineralization or alkaline stage
The APEC RO-90 is one of the top-notch reverse osmosis filtration systems available from a high-end filtration brand. While it is nearly identical to the ROES-50, there is one difference that makes this system better for larger households. RO-90 is rated for 90 GPD, which is the highest rating given to any water filtration system. The filter and housing system for this water filter is also one of the most advanced that we’ve seen. However, it’s still evident that the filters in the first three stages will need to be replaced. These are just smaller than other carbon filters and will likely need to be replaced around the 6-month mark.
This is a compact system so it’s designed to be installed in a small corner of your under sink cabinet space. This system requires a water line and takes about an hour to install. We found that it was easy enough to hook up the water system without any plumbing experience. The water tasted clean and refreshing and tested negative for over 150 contaminants, including lead, chlorine, petrol chemicals, nitrates, pesticides, herbicides, and fluoride.
- Rated for 90 GPD
- Gets rid of 99% of contaminants
- RO membrane designed for 2 to 3 years capacity
- 4-gallon storage tank
- 1 year limited warranty
- Quite large, will take up considerable room under your cabinet
The Home Master TMHP is a top-rated water filtration system that uses reverse osmosis and active carbon filters in its 9 stage process. This is the most processes that we’ve ever seen for a water filtration system, and the result is an entirely pure, alkaline glass of water. This system also includes a permeate pump to increase the output to 75 GPD, and you can also see that it reduces water waste.
The UV light also kills 99.8% of all microorganisms that may be lurking in the water as well. The remineralization process adds safe minerals to your water, allowing you to raise pH for alkaline results. This drinking water tasted the best out of all that we tested.
- An incredible 9-stage filtration process
- Adds minerals and raises pH for alkaline results
- 75 GPD
- NSF and Ansi certified
- Quite expensive due to the permeate pump
One of the more historic brand names on our list is the RO system from Whirlpool. We liked that this reverse osmosis system was very well-designed and included a rather large tank. It’s also easy to install and replace the filters in this design, so we appreciate the efforts that Whirlpool took to create something that works and feels effortless.
In our testing, the water tasted great and had no odor. Almost all of the chemicals we tested were removed, including cysts, lead, fluoride, chlorine, arsenic, and petrol chemicals. However, it doesn’t have a remineralization stage. This filter only uses three stages, which means that the water isn’t as pure as the Home Master.
- Very affordable
- Easy to install and replace filters
- EZ Change Indicator Lights
- NSF certified
- Doesn’t have remineralization process
- Only 3-stage filter process
AquaTru makes one of the only effective reverse osmosis countertop filtration systems in the world. It’s more convenient if you don’t want to install anything, but you will likely have to wait for the water to go through the stages before drinking it unless you always keep it filled. We liked that the water tasted great, and you can control the alkalinity of the water as well.
This is a great water purifier for your office or home kitchen, as long as you have the counter space. It’s also NSF certified and is able to remove chromium 6, herbicides, pesticides, fuel additives, rocket fuel, fluoride, odors, and radium. We felt that the water tasted refreshing and had zero odors, and it tested negative for over 150 chemicals.
- Portable and lightweight design
- No need to install under the sink
- NSF certified
- Customers reported that the base leaked
- Requires you to fill it up and store water without refrigeration
The APEC portable RO countertop is an auspicious appliance for travelers because of its lightweight, portable design. While it is an RO water system, you will need to set it up on your counter near your faucet, and it can look quite out-of-place as it takes up so much room. While it doesn’t require any installation, it’s not compatible with specialized, modern faucets.
You’ll get 90 GPD with this four-stage RO countertop filter. It works for any water pressure between 40 and 80 PSI. It’s also NSF rated to remove most contaminants. However, you’ll probably want to upgrade to a calcium carbonate filter so that it can add minerals back to your water.
- Portable and lightweight
- Removes 99% of all contaminants
- No installation
- Bulky design, needs counter space
The PuricomUSA Zero Installation Purifier is a countertop RO water filtration system that truly looks unique and cool in your kitchen. This modern water purifier is so easy to use and requires no installation whatsoever. There are no hoses, and it’s easy to fill it up. It’s rated to remove 99% of all contaminants as well.
We like that you can also change the alkalinity of the water, allowing you to balance the acidity and get minerals back into your water that are healthy for your body. Overall, we felt that it rivaled the taste of Home Master and other higher quality multi-stage RO purifiers.
- Great design
- Very portable and lightweight
- Requires no installation
- Removes 99% of all contaminants
- Takes up some counter space
Buying the right RO water filter for your home really depends on the taste and quality you are looking for. If you want something that includes a permeate pump and a higher amount of filtration, then you are probably thinking of getting the Home Master RO filter. However, this one can be expensive and may not be the most effortless to set up.
We recommend that those who want to start out with RO try the APEC Top Tier 5-Stage first. This is a great filter that provides clean, pure water that is free of contaminants and tastes amazing.