12 Best Reverse Osmosis System in 2020 – (Reviews & Guide)

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Written by Eric

Last Updated: 11/12/2020

Reverse Osmosis System

Regular tap water can often lead to a number of diseases and health problems due to various contaminants. In such a case, you might turn to bottled water for pure and safe drinking water. However, we’re sure you’ll be heavily disappointed. Apart from the hassles and the environmental problems that come with bottled water, it is mostly filtered tap water.

Filtering tap water in this way fails to remove microorganisms as well as other contaminants, and thus, it can cause you harm in the long run. So, what’s the solution? A reverse osmosis system can help you convert unclean tap water into safe and pure drinking water.

This process involves various stages of filtration where all the contaminants are removed, including bacteria, viruses, heavy metals, and total dissolved solids, just to name a few. This results in tap water that is nothing but pure.
With so many RO water systems on the market, how do you choose the one that suits your needs perfectly? To help you find the best reverse osmosis system, we have reviewed our top choices. Our reverse osmosis system reviews will help you figure out how each system performs and how well it fits your needs.

A 5-Second Glance at the Products

APEC ROES-75 5-Stage Reverse Osmosis Drinking Water Filter System
  • 4.5 Customer Rating
  • APEC Water Systems ESSENCE ROES-50
  • Filtration Process: 5-stage
  • Dimension: 5.2 x 16 x 17.5 inches
  • Item Weight: 26 pounds
  • Pattern Name: 50 GPD
  • Warranty: 1 Year APEC

APEC ROES-PH75 Alkaline Mineral pH+ Reverse Osmosis Drinking Water Filter System
  • 4.5 Customer Rating
  • APEC Water Systems ESSENCE ROES-PH75
  • Filtration Process: 6-stage
  • Dimension: 16 x 5.2 x 17.5 inches
  • Item Weight: 25 pounds
  • Pattern Name: 75 GPD
  • Warranty: 2 year extended manufacturer warranty

iSpring RCC7AK 6-Stage Under Sink Reverse Osmosis Drinking Water Filter System
  • 4.5 Customer Rating
  • iSpring RCC7AK
  • Filtration Process: 6-stage
  • Dimension: 14.5 x 6 x 17 inches
  • Item Weight: 20 pounds
  • Pattern Name: 75 GPD
  • Warranty: 3-year manufacturer warranty

Home Master TMAFC-ERP Artesian Undersink Reverse Osmosis Water Filter System
  • 5 Customer Rating
  • Home Master TMAFC-ERP
  • Filtration Process: 7-stage
  • Dimension: 12 x 16 x 20 inches
  • Item Weight: 14.5 pounds
  • Pattern Name: 50 GPD
  • Warranty: five-year limited warranty

Geekpure 5-Stage Reverse Osmosis Drinking Water Filter System
  • 3.5 Customer Rating
  • Geekpure
  • Filtration Process: 5-stage
  • Dimension: 17.5 x 11.8 x 22.1 inches
  • Item Weight: 24.9 pounds
  • Pattern Name: 75 GPD
  • Warranty: 1year limited

APEC Water Systems RO-90 Reverse Osmosis Drinking Water Filter System
  • 4.5 Customer Rating
  • APEC Water Systems RO-90
  • Filtration Process: 5-stage
  • Dimension: 16 x 5.2 x 17.5 inches
  • Item Weight: 25 pounds
  • Pattern Name: 90 GPD
  • Warranty: Manufacturers

Best Reverse Osmosis System Reviews

APEC ROES-75 5-Stage Reverse Osmosis Drinking Water Filter System

  • 99% removal of all contaminants including arsenic
  • Double carbon blocks with a vast contact area
  • Lead-free water tap design
  • A sufficient capacity of 75 GDP
  • 5-stage filtration process

APEC ROES-75 5-Stage Reverse Osmosis Drinking Water Filter SystemThe APEC Filter System is one of the most renowned systems on the market due to its high-quality filtration technology and its low price. The super-efficient system includes high-quality components such as the APEC Double Carbon Blocks, which ensure pure drinking water straight to your kitchen. In fact, the 5-stage filtration system removes up to 99% of all contaminants including heavy metals, bacteria, lead, chlorine, fluoride, etc.

The carbon blocks include a unique design that maximizes the contact time of water and ensures maximum removal of all contaminants. Furthermore, the 75GPD capacity of the RO system is quite sufficient to fulfill your daily needs.
Moreover, the superior quality filters add to the durability and longevity of the APEC system. Worried about a noisy filter that disturbs everyone around it? Luckily, the APEC Reverse Osmosis system is noise-free and ensures the quietest operation.

In addition, the filter includes a lead-free water tap which features 360-degree rotation. The lead-free design further ensures the purity of the water. A leak-proof seal grants you peace of mind, as you don’t have to worry about ill-fitting pipes or leakages. Lastly, the system is easy to install and maintain.
All in all, the APEC ROES-75 Reverse Osmosis system ensures that you can see and taste the difference in your water.

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APEC ROES-PH75 Alkaline Mineral pH+ Reverse Osmosis Drinking Water Filter System

  • Removes 99% of all contaminants
  • 6-stage operation
  • Enhances the alkalinity of the water
  • Lead-free faucet design and FDA-approved tubing
  • Includes US-made cartridges with food-grade calcium for safer pH enhancement

APEC ROES-PH75 Alkaline Mineral pH+ Reverse Osmosis Drinking Water Filter SystemAnother high-quality product from APEC, the ROES-PH 75 minimizes contaminants in your waterand also improves its alkalinity. The 6-stage reverse osmosis system can help remove 99% of all impurities including bacteria, dirt, chemicals, etc. The capacity of the system is about 75 GPD to fulfill all your daily needs.

The best part is that you can install the system by yourself without any external help. In fact, you’ll find it is as easy to maintain as it is to install. Moreover, the double carbon blocks help remove 99.99% of chlorine and other chemicals in the water. In addition, their large surface area increases the contact time with water.

For safer pH enhancement, the system includes US-made calcium cartridges to improve alkalinity. These add calcium carbonate to the water at the last stage of purification, granting it a taste similar to mineral water. Furthermore, this reverse osmosis system ensures noise-free operation so you can enjoy your peace of mind.

Also included is a lead-free faucet, as well as FDA Certified tubing to ensure pure and safe drinking water. The leak-proof seals and quick connect fittings ensure no leakages occur. Thus, unlike many other brands, you won’t need lock clips or leak detectors. The APEC ROES-PH75 is the perfect choice for those who want to enjoy the taste of pure, alkaline, or mineral water.

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iSpring RCC7AK 6-Stage Under Sink Reverse Osmosis Drinking Water Filter System

  • The 6-stage process includes re-mineralization
  • RO filter removes up to 0.0001-micron contaminants
  • European-designed nickel faucet
  • Extremely easy under-the-sink installation
  • Quick-fitting and leakage free pipes

iSpring RCC7AK 6-Stage Under Sink Reverse Osmosis Drinking Water Filter SystemThe iSpring is a six-layered system that provides protection from over 1,000 types of contaminants including asbestos, arsenic, lead, sodium, bacteria, etc. The sixth stage of the process helps re-introduce healthy minerals back into the water that are lost due to the RO membrane. As a result, you get more natural-tasting water that is still pure and clean.

Moreover, this under-sink reverse osmosis water system is quite easy to install. In fact, you can easily DIY it without any help. However, if you do need any help with installation or maintenance, iSpring’s excellent customer service will guide you through step by step. The high-quality components ensure fewer maintenance checks while the clear housing allows for easier inspection.

Furthermore, the leak-free fittings ensure you never have to worry about pesky leakages. The quick-fitting pipes do not include any threaded connections to make installation even easier. However, included is a metal faucet that adds elegance and sophistication to your kitchen.

In addition, the high capacity 2.5-gallon tank makes sure you never run out of pure drinking water. However, the soul of the system is the reverse osmosis filter that removes the smallest of contaminants, up to 0.0001 microns.
In summary, the iSpring is the best RO system for installation under the sink due to reliable and high-quality components.

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Home Master TMAFC-ERP Artesian Undersink Reverse Osmosis Water Filter System

  • Removes 99% of all contaminants and chemicals
  • Includes a permeate pump that increases the flow rate
  • 7-stage filtration process
  • Full contact technology adds minerals twice to the water
  • Long-lasting and easy to change filter design

Home Master TMAFC-ERP Artesian Undersink Reverse Osmosis Water Filter SystemIf you’re looking for clean and pure mineral water on the tap, then look no further. The Home Master Artesian includes an innovative design that delivers high-quality, pure water. What’s unique about the Home Master system is that the process includes a total of seven stages. These stages help remove 99% of all chemicals and contaminants.
Furthermore, the full contact technology adds minerals such as calcium and magnesium to the water twice. This way, you get better tasting water that is healthy and pure. Also included is a non-electric permeate pump that reduces 80% of wastewater and increases water production by 50%. This ensures cleaner water due to the elimination of TDS Creep.

The Home Master Under-Sink Reverse Osmosis System also includes a powerful carbon filtration medium that removes even the most stubborn contaminants. Moreover, the product uses an all-in-one design for its filters that makes changing filters a breeze. These filters last longer than your usual filters, thus you only need to change them once a year.

A Fast Flow RO Kit uses larger fittings and higher flow components that double the flow of the water. Lastly, the under-the-sink installation is easy and fast as well. With such exquisite features, it’s hard to say no to the Home Master Artesian System.

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Geekpure 5-Stage Reverse Osmosis Drinking Water Filter System

  • 5-stage filtration process including reverse osmosis
  • Lead-free, NSF-certified faucet
  • Includes sevenextra replacement filters
  • Filters 99% of all contaminants
  • Easy under-the-sink installation

Geekpure 5-Stage Reverse Osmosis Drinking Water Filter SystemAnother name brand, the Geekpure, pulls out all the stops when it comes to an innovative water filter system. This small reverse osmosis system includes a 5-stage process including sediment filtration, carbon filtration, and an RO process.

The carbon filtration is a 3-stage process that removes all sediments, tastes, odors, and chlorine. The RO membrane filters 99% of all contaminants that are up to 0.0001 microns in size, including heavy metals such as arsenic, mercury,and lead. The thin RO membrane ensures higher water production with about two gallons of wastewater for every gallon of pure water.

Furthermore, it features easy DIY filter installation that you can fit under the sink. If you’re worried about quality, then rest assured that the Geekpure includes high-quality and reliable components. All tubes, tanks, fittings, as well as the RO membrane, comply with NSF and ANSI standards. This ensures healthy and safe drinking water.

Apart from that, this product includes a lead-free faucet that has been inspected by the NSF to ensure clean water at every stage. It includes a mounting range of 0.5 to 1.5 inches.

Furthermore, all the filters are BPA-free and the manufacturer goes as far as to provide you with seven extra filters in case you need to replace them. Moreover, each filter is quite durable and lasts at least two years, ensuring fewer maintenance needs.

This is, without a doubt, a well-built system that ensures complete purification of drinking water while complying with all safety standards.

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APEC Water Systems RO-90 Reverse Osmosis Drinking Water Filter System

  • Super-efficient double APEC carbon blocks
  • 5-stage filtration process
  • Conforms to the industry standard WQA Gold Seal
  • 90 GPD capacity
  • Lead-free elegant chrome faucet

APEC Water Systems RO-90 Reverse Osmosis Drinking Water Filter SystemThe RO-90 by the APEC is one of the best RO systems in terms of reliability and design. Designed, manufactured, and assembled in the US, you can expect only the highest quality from the RO-90. In fact, even the filters are made within the US to guarantee healthy and safe water.

This filter utilizes a 5-stage filtration process that helps remove all sediments at the first stage while the second and third stages work to remove all odors, tastes,and suspensions. The fourth stage is the reverse osmosis stage, which includes a filter to remove all kinds of metallic components. Lastly, the fifth stage further removes any leftover contaminants.

This premium reverse osmosis water filtration system conforms well to the industry WQA Gold seal, which ensures the maximum removal of all impurities including taste and odor. The high capacity filters have become an industry standard and last twice as long as other name brands.

What users might love is the sleek and elegant chrome faucet that will fit well with your modern kitchen. Not only is it stylish, but it’s also lead-free, ensuring maximum safety. Another great addition to the home reverse osmosis system is the FDA certified, food-grade tubing that provide safe and pure drinking water.

So, for those who are looking for a countertop reverse osmosis filter for the whole house, the RO-90, with its 90 GPD capacity, will serve them the best.

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iSpring 5-Stage Prestige Reverse Osmosis Drinking Water Filter System – RCC7

  • Removes 99% of over 1,000+ contaminants
  • Gold certified WQA against NSF and ANSI standards
  • 5-stage filtration process
  • Includes both GAC and CTO filters
  • Easy and quick installation

iSpring 5-Stage Prestige Reverse Osmosis Drinking Water Filter System – RCC7Another under-the-sink model, the iSpring Prestige RCC7 Water filter system, utilizes five stages to ensure pure, clean, and healthy drinking water. In fact, this product effectively removes 99% of about 1,000 contaminants including asbestos, calcium, fluoride, and even bacteria.

Most users might be skeptical about systems without any standards or certificates. This is why the iSpring RCC7 has been tested vigorously and certified gold by the WQA against NSF and ANSI standards. Furthermore, this under-sink reverse osmosis system is easy to install, typically taking an hour or two. However, if users run into any trouble, the company’s 24/7 customer support can help them out of any snag.

Moreover, the first-stage filter is made transparent to allow for easier maintenance checks. This way, you’ll always know when to change the filter. The installation is completely leak-free as the tubing includes no threaded connections.Instead,it uses quick-fitting locks and connectors.

What’s unique about the system is that it has both GAC and CTO filters. The GAC filter effectively removes the larger contaminants while the CTO filter traps any remaining smaller particles. This not only results in increased efficiency but also longevity and durability. In addition, this RO system also includes a nickel faucet that is stylish and elegant.
The iSpring Prestige RCC7 Filter System offers the best price for high-quality components. With easy installation and efficient filtration, it’s a hard deal to pass up on.

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Express Water Reverse Osmosis Water Filtration System

  • 5-stage filtration process
  • Easy and simple installation
  • Includes granular carbon as well as carbon block
  • Leak detector included
  • Double-sealed filters for longevity and efficiency

Express Water Reverse Osmosis Water Filtration System – NSF Certified 5 Stage RO Water Filter System with Faucet and TankIf you’re looking for a lower filtration capacity, then the Express Water RO System is bound to serve you well. The system effectively removes up to 99.99% of all lead, chlorine, fluoride,and arsenic to ensure you get the purest and freshest drinking water.

This 5-stage filtration system ensures no stone remains unturned in removing all contaminants. The fourthstage includes an RO membrane that focuses on the most stubborn heavy metals, such as arsenic and lead. Additionally, the block and granular carbon filters remove all odor-causing compounds as well as chlorine. This ensures the safest and best-tasting drinking water available to you right from your tap.

Furthermore, you won’t waste any money on professional installation. The design is easy and quick to understand,thus, you’ll find it takes merely an hour to set up. Also, it automatically fills the water tank when it is running empty, so you won’t have to worry about refills or reactivation.

In case you’re worried about leaks, the Express Water RO system includes a leak detector that detects any undesired water and alerts you. Moreover, each filter is double-sealed.This adds efficiency to the process and increases the life of each filter.

With 50 gallons of water per day, the Express Water RO System’s unique design and efficient filtration process is undoubtedly the best on the market.

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Global Water RO-505 5-Stage Reverse Osmosis System

  • 5-stage filtration process
  • Includes four extra filters
  • Includes lead-free and ANSI/NSF-compliant faucet and tank
  • Leak-free quick connect fittings

Global Water RO-505 5-Stage Reverse Osmosis System Water Quality FilterIn the lineup for the best reverse osmosis water system, who can forget the Global Water RO-505? Another name brand, this high-performance filtration system ensures purified water right at your home at an affordable price.
This system effectively removes all kinds of contaminants by about 99%, including arsenic, lead,and bacteria. The high-quality filters reduce the number of dissolved solids and dispose of them. Moreover, they last up anywhere from 6 to 12 months without needing a change. In case you do need a change, the package comes with four extra filters including a GAC, CTO, sediment, and inline filter.

The system also includes an elegant lead-free faucet that complies with NSF and ANSI Standard 58. This ensures cleaner and safer drinking water out of your tap. Furthermore, the tubes include quick-connect fittings that are self-secure and require no external locks or clips to prevent leakages.

Utilizing a 5-stage filtration process, this RO water system ensures the most tasteless and odorless water of any other. The GAC and CTO filter work together to remove contaminants of all sizes, including chlorine, VOCs, odors, and various flavors. Afterward, the supreme-quality TFC RO membrane removes all heavy metals as well as salts and other dissolved chemicals. The end result with the Global Water RO system is pure, clean drinking water that is healthy and safe, all at once.

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Home Master TMHP HydroPerfection Undersink Reverse Osmosis Water Filter System

  • 9-stage filtration process
  • Includes a Re-mineralizer as well as a UV light
  • Modular one-piece long-lasting filter design
  • An iron pre-filter removes dissolved iron
  • Permeate pump that maximizes water pressure

Home Master TMHP HydroPerfection Undersink Reverse Osmosis Water Filter SystemThe Home Master TMHP falls under the high-end price range, however, its extensive features truly justify the high price. Its innovative design, coupled with the efficient filtration capabilities,ensures that you get the safest and purest drinking water right from your tap.

Its advanced nine-stage filtration and enhancement processes ensure exceptionally pure drinking water. The nine stages include a sediment filter, catalytic carbon filter, iron filter, RO purifier, re-mineralizer,and pH enhancer. It removes 99% of all TDS, metals, chemicals, and various other contaminants.

The superior iron filter removes all dissolved iron from the water while the advanced UV light destroys all viruses, bacteria, as well as other microorganisms. The carbon pre and post filters play a huge role in reducing chlorine, which can cause various diseases when ingested.

Moreover, the mineralizer adds healthy minerals into the water to increase the pH. Lower pH can result in acidity and tank degradation. Furthermore, it can heavily affect the taste of the water. Unlike the usual canister filter housing design, the Home Master uses a one-piece modular filter design that ensures scaling doesn’t occur.

All in all, whether it’s well water or city water, the Home Master Undersink Reverse Osmosis System ensures safe and highly pure water.

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Whirlpool WHER25 3-Stage Under Sink Reverse Osmosis Drinking Water Filter System

  • 3-stage filtration system
  • NSF certified for lead removal
  • Under-sink easy installation
  • EZ Indicator Light alerts you when it’s time to change the filter
  • Long-lasting filters with Ultraease technology

Whirlpool WHER25 Reverse Osmosis (RO) Filtration System With Chrome FaucetA small reverse osmosis system, the Whirlpool WHER 25 is perfect for point-of-use applications. It is available at an extremely affordable price and only includes three stages of filtrations. This is perfect for those who wish for high-quality water without sacrificing their budgets.

With long-lasting filters, the WHER25 is NSF certified to reduce 99% of all lead contamination. Most users will find that the 3-stage filtration system is quite sufficient for most contaminant removal. In addition, it helps save space and costs due to the smaller number of filters.

Furthermore, this system is easier to install under the sink due to itscompact size. The improved design includes color-coded tubing, making it easier for you to follow instructions. For the ease of users, this product includes Ultraease technology,whichensures easier filter changes at just a quarter of a turn.

An EZ Indicator Light alerts you immediately when the filter is clogged and needs changing. This effectively removes all guesswork and ensures safe and clean drinking water. The WHER 25 system is an effortless model that uses long-lasting filters to ensure fewer maintenance checks.

Whirlpool is a name you can trust in the water filter industry. Its highly reliable products and components ensure safe and healthy tap water.

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Express Water Alkaline Reverse Osmosis Filtration System – 10 Stage

  • 10-stage process including enhancement, RO, and re-mineralization
  • Leak Stop valve detects the leak and stops it
  • Daily capacity of 100 GPD
  • Long-lasting and easy to change filters

Express Water Alkaline Reverse Osmosis Filtration System – 10 StageWhere other systems might be flushing all the essential minerals down the drain, the Express Water Alkaline RO Filter System ensures the highest quality, pure, alkaline water for the whole house. It includes a 10-stage reverse osmosis water filtration process that helps reduce all kinds of contaminants such as lead, arsenic, bacteria, etc. You might expect a high price tag with the 10-stage process, however, the Express Water system is surprisingly inexpensive, costing less than $200.

Not only that, but it adds more oxygen into the water while the re-mineralizer enriches the water with essential minerals such as potassium, calcium, and magnesium. Furthermore, the RO water filters are double sealed, which helps enhance their life. A Leak valve automatically shuts off in case it finds an excessive flow of water.

You’ll also note that changing filters is quite easy and requires only a few minutes. However, due to the long life of the filters, you won’t find yourself changing the filters too often. With a large daily capacity of about 100 GPD, the Whole House System can provide sufficient water to satisfy your entire household.

The Express Water Alkaline RO Filtration System, with its affordable price tag, is literally a steal. Its quick and easy filtration and enhancement capabilities ensure safe and healthy drinking water.

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What is Reverse Osmosis?

Reverse osmosis, commonly abbreviated as RO, is the process of demineralization and deionization of water by pumping it through a semi-permeable membrane called an RO membrane.

To understand the RO process, we recommend you first understand what osmosis is. Osmosis is a natural process that occurs when two solutions of varying concentrations come in contact with each other through a partially permeable membrane. This results in the movement of ions and other impurities from the dilute side to the more concentrated one. The membrane only allows some particles to pass through it.

The RO process, as its name suggests, is basically the osmosis process in reverse. However, the major difference is that where osmosis is completely natural, reverse osmosis requires the application of external energy. It includes an RO membrane that only allows water to pass through it. Thus, you apply a ‘push’ to the more impure water to allow the exchange to take place.

When pressure is applied to the more concentrated solution, the water molecules move through the semi-permeable membrane while all impurities and contaminants are held back.

How Does Reverse Osmosis Work?

The reverse osmosis process includes a permeate pump that increases the pressure towards the more concentrated or more saline side of the water. This high pressure pushes the water against the RO membrane and through it. This tends to leave behind almost all of the dissolved salts and other contaminants in the wastewater stream.

The concentration of the saline water determines the amount of applied pressure. Generally, if the concentration is higher, you might need a stronger pump for higher pressures. The pressure should be sufficient to overcome the natural osmotic pressure, otherwise, reverse osmosis might not take place.

As pressure is applied to the water, it enters the membrane and passes through it, while salts and other minerals are not allowed to pass. They are discharged back into the feed to be recycled or disposed of completely.

An imperative point to note is that the RO water system utilizes cross filtration rather than standard filtration. In this cross filtration process, the solution passes through the filter with two separate outlets. We know what you’re thinking:“How is this better than standard filtration?” Well, since all contaminated water is discharged, no build of impurities takes place on the filter. This adds to the longevity of the filter and reduces the need for maintenance.
On the other hand, standard filtration allows impurities to deposit on it and requires regular inspection and filter changing.

What Does Reverse Osmosis Remove?

A reverse osmosis water filter removes about 99% of all dissolved salts, bacteria, organics, colloids, particles, and pyrogen from the water feed. Since the process uses a semi-permeable membrane, it rejects the contaminants based on their size. These membranes come in various sizes and each size acts like a sieve. Larger-sized membranes allow larger particles to pass through while smaller ones block these effectively.

Thus, you’ll find that the RO membrane effectively removes all heavy metals that have a molecular weight of greater than 2,000. Apart from size, the RO membrane also rejects particles on the basis of their ionic charge. The greater the charge on the particle, the more likely the membrane will reject it.

This might be a disadvantage, as the RO system is not able to remove calcium or sodium salts that have a very low charge, or gases such as CO2. Due to this, you might find that the purified water includes high levels of carbon dioxide as well as a low pH. The water might be slightly acidic as a result of the reaction between CO2 and water to form carbonic acid.

Reverse Osmosis Water Benefits

Here are some reasons why reverse osmosis water is the best for you:

1. Removes Impurities

Drinking contaminated water can adversely affect your health. Doing socan end up in various gastrointestinal problems as well as various water-related diseases such as cholera, diarrhea, etc. You might be inclined towards bottled water, but can you absolutely trust it? Let’s not forget the hassle of buying it every other week.
With a reverse osmosis system by your side, you can remove these contaminants and enjoy risk-free tap water. As we already mentioned, the system removes about 99% of all contaminants including heavy metal and even bacteria. You’ll find that most of our top 12 RO water filter systems are tested and certified to remove the following:

  • Lead
  • Arsenic
  • Fluoride
  • Copper
  • Nitrates
  • Nitrites
  • Chromium
  • Barium
  • Selenium
  • Asbestos
  • Bacteria and viruses
  • Chlorine
  • Total Dissolved Solids
  • Cyst
  • Radium and other radioactive compounds

2. Reduces Sodium

While you might find a lot of water softeners available on the market, they might not completely purify your water. They do remove most of the hard minerals and make water viable for laundry, cleaning,and bathing, however, everyone might not fancy the taste of soft water.

This is because water softeners exchange the hard minerals such as calcium and magnesium with sodium. So, the total dissolved solids in your water remain the same and thus, you get water that has a specific taste to it.
RO systems effectively filter out all such dissolved solids, including sodium, to ensure that your water is absolutely tasteless. However, we recommend going for a system that couples a water softener and an RO membrane for more efficient filtration.

3. Better than Bottled Water

Bottled water contains a plethora of minerals that might be beneficial to your body. However, you might not prefer the taste of it. Additionally, buying bottled water is a hassle and can be quite expensive. Oftentimes, bottled water is just filtered water packed into bottles. It might still contain harmful heavy metals such as arsenic and lead.

Moreover, water bottles tend to create a lot of plastic waste. Thus, if you care about the environment, an RO system might help you do your part. What’s more is that an RO system only requires a one-time purchase. After you’ve set it up, it will simply use the water from the tap and purify it.

4. Better for Cooking

When you cook food, the most frequently used ingredient is water. Making soups, pasta, bread, gravy, rice etc. all require some amount of water to properly cook. If the water you use has a certain taste to it or if it includes harmful chemicals, then it might affect your food as well.

Using regular tap water is a big no-no as it contains a vast amount of chlorine. It tends to cause a weird taste as well as discoloration. So, we recommend using tasteless water from an RO system,which ensures better taste and color.
Even tea or coffee results in better flavor when made with reverse osmosis water.

5. Clearer Ice Cubes

While this may be a more aesthetic reason, it still counts. You might have noticed how your ice cubes tend to look white and cloudy. The main reason is that impurities and gasses in your water tend to crystallize as your water freezes. Impurities are thus forced to the center of the cube where they form the white cloudy substance.

However, if you use an RO system, it will effectively remove all such impurities, resulting in crystal-clear ice cubes. With attractive and eye-catching cocktails, you’ll be sure to win over all your guests.

Apart from the aesthetics, the clear ice cubes possess a distinct advantage. They not only look more fantastic, they melt slower and are harder than cloudy ice cubes. As a result, they keep your drink cooler for longer without watering it down.

6. Refreshing Taste

The water from an RO system might taste different to you at first. Nevertheless, the refreshing taste is sure to win you over soon. Most RO systems include various filtration stages; three of these include carbon filters that help remove tastes and odors of all kinds.

Are There Any Disadvantages to RO Systems?

There are a couple of disadvantages that individuals often point out. These are:

1. Removal of all Healthy Minerals

While many critics seem eager to dispel RO filtration systems as unhealthy, they refuse to acknowledge the simple solution to the problem. They are quick to note that most 5-stage RO filtration processes that do not use a mineralizer or pH enhancer produce water that has almost no minerals.

Minerals such as calcium, sodium,and magnesium are required by our bodies in trace amounts. Since the RO process removes all these minerals, your body might face deficiencies. It might seem like a valid argument, but critics fail to note the word ‘trace.’ Our bodies only require a very small amount of these minerals, and this amount is almost always fulfilled by our food.

Moreover, since these minerals are in their organic form, our bodies might have trouble absorbing them. In case you’re still concerned about your mineral intake, simply use a 6 or 7-stage Reverse Osmosis system. The sixthstage is the re-mineralization stage, where beneficial minerals are added to the water to enhance its health benefits.

2. Waste of Water

RO systems discharge the highly concentrated water after it has passed through the membrane. Most users believe this water is useless, and thus is wasted. Compare that to a standard filtration process where almost all the water is purified and used.

However, water waste is completely dependent on the user. You can choose to recycle the water again or you can use it for purposes other than drinking. It might not be suitable for drinking, but you can use it for laundry, bathing, watering plants, washing utensils, etc.

Typical RO System Process

The typical reverse osmosis water filtration system doesn’t just involve a reverse osmosis process. Instead, it involves various steps before and after, each of whichadds to the purity of the water. Most reverse osmosis machines include the same first five processes. However, they might add one or two extra processes to enhance the quality of the water.

Here is a step-by-step guide to a typical reverse osmosis process:

Step 1: Sediment Filtration

The first step involves the removal of all sediments and larger particles such as dirt, dust, stones, clay, rust, etc. Typically, a 5-micron filter is used for the first step so any particles larger than this will be suspended out.

Step 2: Granulated Carbon or GAC Filtration

The second step uses granulated carbon,which effectively removes all smaller particles that may have been missed by the sediment filter. Furthermore, it removes harmful chemicals from the water, including chlorine and other odor-causing chemicals. This helps in stripping away any taste and odor from the water.

Step 3: Block Carbon or CTO Filtration

The next step also involves a carbon filter, however, this carbon is more compact and solidified. It further removes any particles or sediments as well as taste and odor-causing chemicals.

Step 4: Reverse Osmosis Filtration

This is basically the heart of the reverse osmosis water filtration system process. The water passes through the reverse osmosis membrane in this step. This semi-permeable membrane can be up to 0.0001 microns in size. Thus, it effectively removes even the smallest of particles. Moreover, as we already explained, the membrane also sorts the contaminants according to their charge and weight.

Any elements that are larger than 0.0001 microns in size are removed, along with those whose molecular weight is higher than 200. The filter further removes all substances with a high ionic charge along with almost all radioactive compounds. The result is water free for all sorts of contaminants.

Step 5: Final Carbon Filtration

For many RO filtration water systems, this may be the last step, while in others, it may be followed by more steps. During this step, all remaining odor, chlorine, bacteria,andflavor is removed from the water. After this step, the water goes to your faucet or your tank and is deemed fit for drinking.

Step 6: Re-Mineralization and pH Enhancement

One of the drawbacks of the RO system is that it removes all minerals even if they are beneficial. Thus, purified water might taste weird to you. Since most people rely on drinking water to get their share of minerals, they might be at a severe disadvantage with a reverse osmosis process.

However, a sixth step can be added to re-introduce the minerals into the water. As a result, you get healthier and better-tasting water. By ‘better,’ we mean water that tastes like bottled or mineral water. In addition, it increases the pH of the water. RO-filtered water might be slightly acidic, which may lead to gastrointestinal problems.

Step 7: UV Filtration

This is yet another added step in the RO filtration process. It is rarely used by many brands and manufacturers. Nevertheless, it is also beneficial and ensures safer and healthier water. It includes a UV filter that reduces the number of micro-organisms including viruses and bacteria in the water.

The UV light is provided by a UV bulb that uses an electrical outlet or a battery as its source of energy. The light kills almost all microorganisms present in the water, thus making it safer to drink and use.

Step 8: Any Step

This may include any step above the seventh step. Some manufacturers divide the re-mineralization process into various steps to ensure more effective removal.

Types of RO Membranes

The most common membranes used in RO filter systems are the Cellulose Triacetate (CTA) and the Thin Film Composite (TFC) membrane. These membranes perform the same functions, however; the only difference is the chlorine tolerance as well as the filtration ability.

The CTA membrane is tolerant to chlorine and can easily treat all kinds of chlorinated water. However, these membranes are more susceptible to bacteria and only remove 93% of all contaminants.

On the other hand, a TFC membrane rejects about 98% of all contaminants. However, it can only be used with chlorine-free water. Furthermore, it is less susceptible to fouling. Also, you might have to add carbon filters to remove chlorine from the water before the reverse osmosis process.

Single-Pass vs. Double-Pass RO Systems

A single-pass RO system only passes the water through the filtration system once. A double-pass RO system passes the pure water produced from the first pass again to ensure purer and cleaner drinking water.

Undoubtedly, water from a double-pass RO system has lesser contaminants and is of a higher quality. In addition, a double-pass system removes all carbon dioxide particles as it injects caustic base in between. As a result, it helps in increasing the pH of the water. The carbon dioxide reacts with a caustic base to form carbonates and bicarbonates.

One-Stage vs. Two-Stage RO Systems

A one-stage system purifies water and produces wastewater and purified water. However, in a two-stage system, the wastewater is again recycled into the filter and is purified. Then, the water leaves as two streams: wastewater and pure water.

Types of Reverse Osmosis Systems

When trying to find a reverse osmosis system, you might come across the following types:

Countertop Reverse Osmosis System

These systems are generally intended to be placed on the countertop or the ground. They are freestanding units that do not require drilling or a complex installation process. Furthermore, they are compact and you can place them anywhere in your kitchen without worrying about space.

These are best for those who do not want to make permanent changes in the kitchen. Thus, renters might find these systems suit their needs better. Furthermore, the elderly can benefit from the simple installation process, as well.


  • Compact and lightweight
  • Can be placed anywhere on the countertop
  • Involves no complex installation process


  • Not easy to use
  • Requires space on the counter

Under-Sink Reverse Osmosis System

These reverse osmosis drinking water systems are installed, as their name suggests, under the sink. They are more commonly found on the market than other types of systems. In fact, most of the products included in our RO water filter reviews are under-the-sink versions. Their installation is a little complex and requires you to mount them under the sink. You might need professional help if you’re not savvy with a drill and hammer. However, once installed, they are extremely easy to use.

These are bigger units than the countertop ones. As a result, they filter larger quantities of water quickly.


  • Easy to use
  • Filters a large amount of water
  • Require no countertop space
  • Hidden from view


  • Difficult installation process
  • Produce more wastewater

What to Consider When Buying an RO Filter System

You might be confused and befuddled due to the large variety of RO systems available on the market. If you’re looking to find the right one, then you might want to consider the following factors:

1. Cost

The reverse osmosis system price mainly depends on the manufacturer and the brand. The cost is the first factor you need to consider. Most reverse osmosis machines cost anywhere between $250 and $500. Some of the higher-cost products might include some extra features or filtration stages. Some expensive models even allow you to re-mineralize your water.

Going with a cheaper option may not be too bad if it fits all your needs. However, the materials may be of cheaper quality and the product might not last long. The mid-range might be sufficient for most users, whereas the high-end products might include extra features that can help you in the long run.

2. Size

The space you have available is yet another important consideration regardless of whether you wish to install a system on the countertop or under the sink. If you have limited counter space, you might want to refrain from adding a large reverse osmosis filter. It will be quite difficult for you to make sufficient space for it.

On the other hand, an under-sink system has to fit under the sink. If you buy a larger unit and you have a small sink, you might not be able to install it properly.

A good idea is to measure the available space before you order. Then you can cross check these dimensions with the dimensions of your system and see whether it fits.

3. Amount of Water

Another important consideration is the capacity of the RO system. This refers to how much water the system can filter. Most manufacturers provide this information in the specs sheet in the form of gallons per day, or GPD.

Generally, you’ll find standard sizes of 50, 80, and 100 gallons. The size depends on the water needs of your home. If you have a small household, then a standard 50-gallon-sized filter may be sufficient. On the other hand, you might want to go for the larger capacity filters for a larger household.

4. Purity and Number of Stages

One of the most important factors you need to consider is how many filtration stages are involved with the product as well as how effectively it removes any contaminants. A typical 5-stage filter removes all dust, dirt, metals, bacteria, viruses, etc. It includes a sediment filter and two carbon filters, as well as a reverse osmosis membrane and a post-carbon filter.

This results in exceptionally clean and pure water. However, some manufacturers add extra steps to either add more minerals or remove more impurities. Generally, the more the number of stages, the purer your water will be. Most manufacturers claim that their system can remove 99% of all impurities. We recommend you properly research their claims before giving into them.

5. Installation

If the installation of a particular system is especially difficult, you might end up calling professional help. The complexity of the installation may affect the cost of services. Thus, we highly recommend that you go for a system that is easy to install.

In fact, we highly recommend that you buy a unit that you can easily install yourself. Under-sink units are harder to install since they include mounting the unit and drilling into the wall.

6. Ease of Use

Most reverse osmosis units include a simple operation. You simply need to connect the water supply and turn the filter on. Then, all you need to do is turn on the tap to enjoy pure drinking water. However, the system may require frequent checks to ensure the filters are working properly.

In case, you feel that the filters are clogged, you might need to replace them. Ensure that the system is easy to clean and does not involve a lot of hassles. We recommend models that have long-lasting filters that require changing once a year.

Regular maintenance and inspection is a must for any RO filter system, however, you should ensure that the work is minimal.

7. Wastewater

An RO system usually generates some amount of wastewater that is higher in concentration. Most systems might not be able to recover even 50% of the water. Most manufacturers display this information in the form of a wastewater ration. For example, if your system has a wastewater ratio of 1:3, this means that it produces three gallons of wastewater for every gallon of fresh water. The recovery ratio is about 25%.

However, some systems further recycle the wastewater back into the system for more efficient recovery, while others recycle it towards cleaning your laundry. These systems are called zero-waste systems. This wastewater is simply high in sodium and other salts. It is perfectly safe for other household chores.

8. Longevity

If you’re investing a huge sum of money into your RO filter system, then you need to ensure that it will last a long time. Usually, popular brands provide the best longevity and durability, as they include high-quality materials and filters. You can try looking for a system that includes a long warranty or even a lifetime warranty.
This ensures you won’t have to deal with broken parts. Instead, you can just get them repaired directly by the manufacturers.

Understanding RO Terms


TDS is an abbreviation that stands for Total Dissolved Solids. These usually include salts such as magnesium, calcium, potassium, chlorides, sulfates, sodium, etc. Apart from these inorganic salts, they also contain trace amounts of organic matter. The recommended TDS level in drinking water, as suggested by the EPA, is about 500mg/L.

You can measure the TDS level in a lab, which can be quite expensive. The other method is by using the principle of electrical conductivity. This method is inaccurate, nevertheless, the method is quite inexpensive.
An RO system should reduce the TDS in drinking water by at least 90%. If your system’s reduction rate decreases, you might need a filter change.

Air Gap Faucet

An air gap faucet provides you with a siphon break. It is usually used with under-sink RO systems. The air gap faucet is actually a fail-safe which ensures that in case of a backup, none of the dirty water gets siphoned back into the RO system.

It is possible that your RO system comes with an air gap faucet, however, most manufacturers include a non-air-gap faucet in the package. The products included in our reverse osmosis water filter reviews do not include an air gap faucet either. We highly recommend that you add an air gap faucet as it ensures longer life of the RO membrane and fewer maintenance needs.

Although they can be a little more complicated to install and they need a larger hole, they still prove to be quite beneficial. Moreover, they can be a little noisy. So, if you don’t mind a noisy unit, then an air gap faucet is the perfect way to go.

Don’t forget to also check out our list of best-selling tankless water heaters, touchless kitchen faucet buying guide, sump-pump reviews and the best commercial faucets of 2019 while also reading more of our products reviews.

Understanding the GPD Rating of RO Membranes

Usually, a reverse osmosis system operates under water pressure from 40 to 100 psi and generates about 10 to 75 gallons per day. However, you are mistaken if you think this is how much your system will produce. In fact, you’ll be surprised to find that your system typically generates only 50 to 75% of the GPD rating.

A GPD Rating is used to rank the system. These ratings are based on tests that manufacturers perform under ideal water conditions, including concentration and temperature. However, the water conditions in your kitchen may differ widely. Cold water can reduce productivity by almost half. Moreover, as time passes, RO membranes tend to clog with contaminants.

This results in reduced production, and you might need to change the filter if you want to increase it. Also, certain particles can cause membranes to wear out quicker, while others don’t.

You’ll be surprised to find that there is a very minor difference between the prices of a lower-producing system and a higher-producing one.

If you wish to use the system for residential use, we recommend you go with a 50 GPD system. This ensures that your entire household can enjoy safe and fresh drinking water. Plus, the higher GPD does not cost significantly more than a lower one. This is especially important in the winter months when the water is colder. So, go for a reverse osmosis home system with a higher GPD.

How to Install an RO Water Filter System

Most RO systems involve fairly quick and simple installation. In fact, all you need to do is connect your faucet inlet with your RO system’s outlet and you’re good to go. You might be able to do so with some simple tools without any professional help at all.

Moreover, these systems come with all the tubing and fittings you need to install the system properly. However, these systems are made for under the sink or countertop installation. So, if you plan on installing them far away from the sink, you might need extra tubing and accessories.

All in all, it takes the following steps to properly install an under-sink reverse osmosis water filter system:

  1. Disconnect and remove the cold water pipe from the wall as well as the faucet.
  2. Your RO system might come with a T-connector along with a push fit connector. Connect the T-connecter and the push fit connector with the coldwater feed outlet
  3. Attach the cold water feed to the T-connector.
  4. Next, drill a hole into the wastewater pipe. This serves as a connection to the filter waste connector. We recommend drilling a hole in the horizontal section of the pipe. This reduces noise.
  5. Attach the connector for the RO drain with the drain pipe using the drill as a guide.
  6. Next, attach the filter to the back of the wall, ensuring there is enough space to remove it later.
  7. Place the tank at the bottom of the sink cupboard.
  8. Attach the faucet onto the sink.
  9. All pipes and tubing included in the package are color coded. We recommend referring to your manual on how to attach these water pipes.
  10. Plug the UV light into an electric outlet, if a UV light is present.
  11. Turn on the water.

Cleaning an RO Membrane

While RO membranes last much longer than traditional membranes and filters, you might still need to change them atleast once a year or sooner, depending on the salinity of the water. If the permeate water salinity is increased by about 15% percent, then you might want to consider cleaning out the membrane.

If your permeate water flow has decreased by 15%, then you should also consider cleaning your filter. You can either choose to clean the RO membrane while it’s still in place or you can choose to remove it completely from the system.
Note that cleaning it off-site is much more effective than cleaning it onsite. The cleaning mainly involves removing contaminants by using low and high pH cleaners. Low pH cleaners target scaling while high pH cleaners target colloids, organics,and bacteria.

However, the chemicals are not the only factors. In fact, you need to take special care of the flow and water temperature as well as the size and design of the skids.

Visit our top rated shower head filters and leak detectors buying guide to see which we think is the very best.

Reverse Osmosis System Comparison Chart

Reverse Osmosis SystemFiltration ProcessPattern NameRatingPrice
APEC Water Systems ESSENCE ROES-505-stage50 GPD9$$
APEC Water Systems ESSENCE ROES-PH756-stage75 GPD9$$
iSpring RCC7AK6-stage75 GPD9$$
Home Master TMAFC-ERP7-stage50 GPD9$$$
Geekpure5-stage75 GPD8$
APEC Water Systems RO-905-stage90 GPD9$$
iSpring RCC75-Stage75 GPD9$$
Express Water5 Stage50 GPD 9$$
Global Water RO-5055 StageN/A9$$
Home Master TMHP9-Stage50 GPD9$$$$

Final Words

Our list of the 12 best reverse osmosis systems is an all-encompassing list that should serve you well. Always remember to first decide what qualities and features you need in a reverse osmosis system, and then make your final decision. Another important aspect is the space available. Most of our reverse osmosis system reviews include under-sink systems, which require sufficient space beneath the sink.

So, ensure you can afford the space before you pick a system. Furthermore, never cross your budget for extra features that are not a necessity. There are various high-quality products that are available at an affordable price, so you don’t need to sacrifice your budget for quality.

All in all, don’t hesitate to ask for professional advice and reach out to these companies to fully learn about their products. Choose only when you’re sure the product will serve your needs and last a long time.



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