2020’s Best Reverse Osmosis Systems | Reviews + Buying Guide: Which RO Water Filter Is Right for You?
Written by: Gene Fitzgerald // Last Updated:
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A proper reverse osmosis system removes almost all contaminants from water, usually at the point of use. The result: Highly pure, healthy, and refreshing drinking water.
Above that, RO systems provide enough filtered water for a whole family. Plus, they’re relatively easy to install and maintain, and cost-effective.
The only problem: How to find a unit that fits your needs? Don’t worry, here’s our collection of the best reverse osmosis systems in 2020.
1. Best Reverse Osmosis System: AquaTru (Including Discount Code!)
In our opinion, the best reverse osmosis system in 2020 is the AquaTru. It’s certified according to official NSF testing standards to remove up to 99.99% of more than 80 water contaminants. In other words, the purified water that comes out of an AquaTru is healthy and safe, and it tastes great!
But this is not even the main reason why we think the AquaTru RO system is the best of its kind. What we love about it is the plug & play functionality. Yep, this countertop unit is completely installation-free – no plumbing, no drilling. This is not only ideal for renters, it also saves you a lot of money if you’re not the kind of person that likes DIY projects. By the way, system maintenance is super simple and low-cost, too. 4.5 stars!
Make sure to use our discount code BOSAquaTru at checkout and get 5% OFF!
AquaTru reverse osmosis system can be set up within a few minutes.
Very easy to use.
Clean water collects in removable front tank (great for cooling) and can be dispensed. Contaminants are captured in back tank ready to be discarded.
Uses combination of sediment and coconut shell activated carbon pre-filter to trap dust, rust, and other large particles, and adsorb bad tastes and odors as well as chlorine (96.6%) and a bunch of chemicals.
Reverse osmosis filter membrane removes heavy metals such as lead (99.1%) and chromium-6 (97.2%), fluoride (93.5%), cyst (99.99%), and TDS (87.1%).
Coconut shell activated carbon block post-filter reduces organics, PFOA and PFOS (97.5%), pesticides, pharmaceuticals, etc. Also filters any residual taste.
4-stage filtration process is NSF Standards 42, 53, 58, 401 and Protocol P473 certified.
Outstanding test results.
Guarantees clean drinking water and the safety of your health.
Uses pressure pump to force water through reverse osmosis membrane.
Fast filtration: The RO system purifies one gallon of water in 10-15 minutes.
Reduces wastewater production. Only 20% of the input water goes down the drain, compared to 3-5 gallons that standard reverse osmosis systems waste for every gallon of filtered water.
System maintenance doesn’t require much time or effort thanks to long-lasting filters that can be replaced with a simple twist.
AquaTru tracks time and the amount of water used to tell you when you need to change one or more of the filter elements. You’re probably looking at annual/biannual replacements. Cost? Around $100-120 per year which is affordable compared to the competition.
All plastic is BPA and BPS-free.
Everything is covered by warranty for one year.
Potential leaking due to design flaw.
Some reviewers said their system malfunctioned after a couple of months use.
2. Best Under Sink Reverse Osmosis System: Aquasana OptimH2O (with Remineralization!)
In our opinion, the best under sink reverse osmosis system in 2020 is the Aquasana OptimH2O. Just like the AquaTru, it’s NSF certified to filter more than 80 water contaminants including chlorine/chloramine (97.66%), mercury (>95.8%), lead (99.3%), VOCs (~99.4%), pentavalent arsenic (97.6%), chromium-6 (97.0%), fluoride (95.7%), overall TDS (95%), BPA (98.9%) and other chemicals, and PFOA & PFOS (96%).
Apart from effective contaminant removal which makes the water safe to drink, the Aquasana OptimH2O RO system also releases healthy calcium, potassium, and magnesium for improved taste and alkalinity.
Did we mention the affordable price and Aquasana’s reliable customer service? Bottom line: 4.5 stars!
Aquasana OptimH2O Under Sink Reverse Osmosis System
Most people are more than happy with their purchase.
3 filtering stages remove 88+ contaminants from water.
Full system is certified according to NSF/ANSI standards 42, 53, 58, 401, and P473 for guaranteed performance.
Uses activated carbon filter to eliminate chlorine and larger particulates.
RO membrane filters out heavy metals, microorganisms, and many other potentially harmful contaminants.
Claryum (filter stage 3) combines activated with catalytic carbon to adsorb pesticides, herbicides, chloramine, a bunch of heavy metals, drug residues, etc.
Additional remineralization stage enriches water with healthy calcium, magnesium, and potassium to improve taste and balance pH.
32 gallons daily filtration capacity is enough water for regular household use.
Recommended operating water pressure: 40-100 psi.
3 full-metal faucet designs to choose from: Chrome, brushed nickel, and oil-rubbed bronze.
RO system can be DIY-installed. All required parts + step-by-step installation instructions are included in the package.
Just make sure to follow every single step as disclosed in the manual. Contact customer service if you don’t know what to do next.
Aquasana OptimH2O reverse osmosis system is easy to maintain thanks to twist on/off filter housings and quick-connect fittings. Annual replacement filter cost: About $180-220 depending on water quality and usage.
More than what you pay with most of the competition.
Join the Water for Life replacement filter program to get discount.
RO system is covered by 2-year limited warranty + 90-day satisfaction guarantee for peace of mind.
A few people had problems with leaking.
Aquasana sends replacement parts free of charge.
Issues with overall quality, especially water dispenser which feels flimsy.
3. Best Reverse Osmosis System for Well Water (Optional UV): Crystal Quest 1000C & 1000CP
In our opinion, the best RO system for well water in 2020 is the Crystal Quest 1000C respectively the 1000CP. The only difference is that the latter comes with a pump in case your water is high in TDS or you don’t have enough water pressure from the well (65 psi is the optimum).
Why these systems? Because they use more than 10 filtration steps to remove all contaminants commonly found in wells and more: Sediment, pesticides, industrial solvents, microorganisms, colloids, volatile organic compounds, PCBs, tastes, odors, metals especially iron, hardness, hydrogen sulfide (rotten egg smell), etc.
And if you want you can add a UV treatment stage on top for 99.99% reduction of bacteria, viruses, and protozoa. This turns the Crystal Quest 1000C into the 3000C, and the 1000CP into the 3000CP.
Please note: According to Crystal Quest, the above systems can handle very hard water with up to 15 gpg hardness. Iron content shouldn’t exceed 2 ppm. This will result in a filtration capacity decrease of no more than 5%. At higher iron/hardness levels, the filters and membranes will clog prematurely. Tip: Contact Crystal Quest live support to discuss custom pretreatment.
Reverse osmosis under sink water filter systems use 12 stages of filtration.
Filter stage 1 is an activated carbon block (5-micron nominal). It adsorbs chlorine and all kinds of chemicals. Furthermore, it traps undissolved matter to protect the following filter stages from clogging.
Stage 2 is a 0.02-micron ultrafiltration membrane. Ultrafiltration is effective for the reduction of microorganisms and other organic and inorganic molecules.
At stage 4, the water passes through granular activated carbon (GAC). Say goodbye to 99.9% chlorine, bad taste and odor, and dozens or even hundreds of chemicals that may be lurking in your water.
Next comes an ion exchange resin. It filters metals – think lead – and water hardness.
Stage 6 + 7 is Eagle Redox Alloy filter media, a blend of copper and zinc. They combine electrochemical oxidation & reduction with adsorption. This takes care of hydrogen sulfide, iron, mercury, chromium, cadmium and other dissolved metals. The media also inhibits bacterial growth throughout the entire system.
The reverse osmosis membrane (stage 9) rejects all particles larger than 0.0001 micron.
And lastly, filter stage 11 is another GAC filter to remove any residual tastes.
Stages 3, 8, 10, and 12 are filter pads. Rated at 1 micron, they remove suspended particles like silt, sand, rust, sediment, and cyst.
Enough output water flow for family use.
Optional: Ultraviolet light filter. Kills 99.99% of bacteria, viruses, and protozoa.
Optional: Nitrate filter. Might be necessary if you live close to agricultural lands or animal feedlots.
Optional: Fluoride filter. For high organic fluoride in well water.
No more difficult to install than other under sink RO systems.
Maintenance requirements are kept at a bare minimum. Cost: $100-155 per year. You can subscribe to save 5%.
The Crystal Quest Thunder is our number one portable reverse osmosis system this year. That’s because it can be attached to any standard faucet in a matter of seconds – at home, in your RV, or while you’re on the move. This plus its compactness make it the ideal travel companion.
Customer satisfaction is high and the price tag is reasonable. Our only issue is that we’re missing NSF testing/certifications with specific contaminant reduction rates. 4.5 stars!
Delicious water, sleek design, straightforward under-sink install, and effortless filter changes – the Waterdrop WD-G3-W is our go-to tankless reverse osmosis system in 2020. No tank means the unit filters water on demand rather than storing it in a tank which saves quite a bit of space under your kitchen sink. Taking into account the high initial purchase price, it’s worth 4 stars from us.
3-layer composite filter (polypropylene cotton + coconut shell activated carbon block) removes chlorine, bad tastes and smell, and sediment like sand and rust.
RO filter membrane rejects harmful metals, bacteria, viruses, and much more.
Another activated carbon block filter gives the water a finishing touch improving aesthetics.
System is NSF Standard 58 certified for 94% TDS rejection.
Built-in pressure pump increases water flow to 0.28 gallons per minute to eliminate long waiting times. One cup fills in little more than 10 seconds.
The pump also reduces the amount of wastewater flowing down the drain from the standard 3-5 gallons for every gallon of filtered water to as little as one gallon.
All plastic is BPA-free to avoid recontamination.
The dispenser is metal for high durability.
Waterdrop reverse osmosis systems can be installed by non-professionals within one to two hours.
You shouldn’t have problems if you’re handy with tools and as long as you follow the instructions provided.
Smart faucet uses LED to indicate filter status. Blue light means your filters are working just fine. When you see yellow light you have less than 40 gallons of filtered drinking water left (about 15 days). Change filters immediately once you see red light and hear beeping sound when dispensing water.
Similar lights are found on system front panel.
You no longer need to remember date of next filter replacement.
TDS monitor on system front panel also indicates filtration effectiveness which is another feature to oversee filter status.
Filter replacements can be done in 10 seconds with no need for tools and closing feed water line. Yearly cost: We estimate roughly $115.
Other important features: Auto-flushing to prevent fouling and leak protection.
Waterdrop WD-G3-W reverse osmosis system comes with a 30-day money-back guarantee that allows you to return the product for a full refund + manufacturer warranty (one year).
High initial cost.
We have little doubt that the Waterdrop is effective but we would have preferred more lab testing.
Some people need to drain a full gallon of water before the system achieves optimum TDS.
6. Best Cheap Reverse Osmosis System: NU Aqua Platinum Series – 5 Stage Water Purification, 100GPD
The NU Aqua Platinum Series 5-stage reverse osmosis system is perfect for people on a tight budget. It comes at a fraction of the cost of what you pay for the units of some of the leading brands. And not only that, you also get free shipping, a TDS meter, a 180-day satisfaction guarantee (refund or credit of original purchase amount if filtered water doesn’t meet your expectations), and a full 5-year warranty. On top of that, replacement filters for one year cost as little as $50 which is unheard of.
How can the Nu Aqua RO system be so cheap? According to the company, that’s because Nu Aqua is the manufacturer of their own products. There’re no middle men so they can offer the best possible prices. We like! 3.5 stars.
The thin-film composite RO membrane rejects even the smallest dissolved solids: Salts, metals i.e. lead, arsenic, fluoride, sulfate, radium…
Before the water comes out of the chrome dispenser it passes through an inline post-filter made of activated coconut shell carbon. It removes any last traces of flavor or odor to make sure you get the freshest possible taste.
High flow membrane (100 gallons of water per day) fills tank in less than 2 hours, perfect for large households with up to 6 people.
All parts are BPA-free to keep water as pure as possible.
Almost anyone can install this RO system in one afternoon. Step-by-step installation DVD and owner’s manual included.
Nu Aqua reverse osmosis systems are “a breeze to maintain”.
Replace filters every 6-9 months and RO membrane every 1-1.5 years.
Replacement sets are super cheap.
TDS meter as free bonus.
Backed by 180-day satisfaction guarantee and full 5-year warranty.
Written installation directions could do with an upgrade.
7. Review: Home Master HydroPerfection (TMHP) Reverse Osmosis Drinking Water Filter System
The HydroPerfection, or TMHP, combines the best of all Home Master reverse osmosis systems such as a thorough water purification process including UV light treatment suited for both well and tap water, remineralization, and a built-in permeate pump which increases total daily water production while reducing wastewater. The result is an unlimited amount of highly purified and great-tasting alkaline drinking water. You just need to be willing to pay a premium. 4.5 stars!
Make sure to use our coupon code BOSFREERO at checkout and get FREE SHIPPING!
Process with 4 Water Filters, Separate Water Storage Tank
Unit Filters Most Contaminants (According to Company Testing Results), Requires Electricity, Easy to Install & Maintain, Carbon Block Filtration
Aquasana OptimH2O Under Sink RO System
4 Filters, Separate Water Storage Tank, Dedicated Faucet
Lower Water Pressure, Filters Most Contaminants (According to Manufacturer Testing Data), Makes Use of Catalytic Carbon, Remineralization Stage Adds Minerals Back to Clean Water (Raises pH), Regular Under Sink Install
Crystal Quest 1000C & 1000CP Reverse Osmosis Systems for Well Water
5 (12) Water Filters, Separate Water Storage Tank, Dedicated Faucet
Filters Hydrogen Sulfide, Regular Under Sink Installation
Crystal Quest Thunder Portable Reverse Osmosis Filter System
5 (10) Filters Process, No Water Storage Tank, Dedicated Faucet
Easy to Install
Waterdrop WD-G3-W Reverse Osmosis System without Tank
3 Water Filters, No Water Tank, Dedicated Faucet
Makes Use of Double Carbon Block Filters, Pump Boosts Water Pressure & Filtered Water Efficiency (Less Waste Water), Easy Installation + Maintenance
NU Aqua Platinum Series 5 Stage 100 GPD RO System
5 Water Filters, Separate Water Tank, Dedicated Faucet
Cheap, Straightforward Installation + Maintenance
Home Master TMHP HydroPerfection RO System
9 Filter Stages, Separate Water Storage Tank, Dedicated Faucet
TFC RO Membrane, Makes Use of Catalytic Carbon, Remineralization Stage Adds Minerals Back to Clean Water (Raises pH), UV Light Filter Kills Bacteria & Viruses + Other Types of Microorganisms, Permeate Pump Boosts Water Pressure & Filtered Water Efficiency (Less Waste Water), Straightforward Installation + Maintenance
Other Reverse Osmosis Water Filter Reviews
Best Countertop and Portable Reverse Osmosis Water Filtration Systems
Compared to the majority of under sink reverse osmosis systems, countertop/portable RO units feature less filtering stages. In return, they’re installation-free. Most can be hooked up to a standard-sized faucet in seconds. Others are standalone and don’t require any sort of water connection at all. This is why this type of RO system is perfect for renters who can’t make permanent changes to their plumbing system. Students and travelers are fond of them, too. Want to know more?
Best Whole House and Commercial Reverse Osmosis Systems
In comparison to POU reverse osmosis systems, whole house or commercial RO systems have way higher filtering capacities, which is important when you consider that they need to treat all the incoming water before it gets distributed throughout a home or office. RO purified water at every outlet – how great is that?! It allows you to drink safely from any faucet, enjoy contaminant-free showers, and the lifespan of your water-using appliances increases, too.
Buying Guide: What You Need to Consider When Choosing an RO System for Your Home
What do you need to consider when searching for the best home reverse osmosis system?
Reverse Osmosis Systems and NSF Certifications
They may be more important with other water filtering solutions, but with RO systems, too, one should choose a unit that’s NSF certified (or tested) if possible. NSF certifications not only ensure that a reverse osmosis system actually performs as good as the manufacturer claims, but also that it’s made from high-quality materials.
NSF Standard 42 tests filtration systems for the reduction of aesthetic non-health-related contaminants, most importantly chlorine. The scope of the standard also includes material safety and structural integrity.
Standard 53 tests systems for the reduction of contaminants with health effects regulated by the U.S. Environmental Protection Agency (EPA). These include cysts, some heavy metals, and volatile organic compounds (VOCs) among others. Again, the scope also covers material safety and structural integrity of a product.
Standard 401 tests filtration systems for the reduction of 15 different “emerging compounds“. These are pharmaceuticals and chemicals that are not yet regulated by the EPA.
Standard 58 is for RO systems specifically. It establishes the minimum requirements for the reduction of a whole range of contaminants, such as TDS (Total Dissolved Solids), chromium 3 and 6, arsenic, nitrate/nitrite, and lead. Material safety and structural integrity are included.
Some reverse osmosis systems are also certified by the FDA which we consider less important.
The Water Filtration Process
Generally, top-notch RO systems feature at least 4 to 5 stages of filtration that water has to pass through before it comes out of the dispenser:
2. Carbon block filters – Remove disinfectants, organics, chemicals, unpleasant odors and tastes, a few heavy metals, and even cysts if the micron rating is small enough.
3. Granular carbon filters – Same as stage 2.
4. Reverse osmosis membrane – The reverse osmosis membrane filters out more or less all remaining contaminants including salts, metals, bacteria, and viruses.
5. Coconut shell post filters – Remove any residual tastes and odors.
Some pricier RO systems come with additional components, for example to remineralize the water and balance pH by adding bits of calcium and magnesium.
Reverse Osmosis System Installation and Filter (Membrane) Replacement
A well-designed under counter reverse osmosis system not only allows for easy installation, it’ll also make filter and membrane replacements way easier (of course the latter also goes for countertop units).
RO water systems that feature a modular design are the preferred choice here. Whenever you replace one of the filters you simply dispose of the entire housing. This prevents bacteria and other germs from accumulating, plus the whole process doesn’t take more than a few minutes. No need to turn off the water supply, no spilling, no worries.
The only drawback: Modular replacement filters can be more costly than those with separate housings.
When to replace the RO membrane? A TDS meter will tell you. Simply measure TDS of both feed water and permeate water. If the rejection rate drops below 80% it’s time for a new membrane.
You can use this formula to calculate your current TDS rejection rate:
Rejection rate in % = (Total Dissolved Solids of untreated tap water – Total Dissolved Solids of pure water) / Total Dissolved Solids of untreated tap water x 100
RO Water Wastage
All reverse osmosis systems waste water. That’s just how the process works. However, a water pressure pump or a permeate pump can reduce water wastage significantly. Some RO systems already have a pump built-in, like the AquaTru. Others can be upgraded.
More on Reverse Osmosis Systems
In the first section, we reviewed the best RO systems currently available on the market. Then we talked about what to look for in a proper unit. Lastly, we’ll answer some common reader questions.
Reverse Osmosis System Cost
How much does a point-of-use reverse osmosis system cost? How much do you have to pay for a whole house RO unit? And what are the costs for installation, maintenance, and operation? All answers in our Reverse Osmosis System Cost Guide!
If you live in a rural area and receive water from a private well you might be looking for a reverse osmosis system that works on wells – makes sense.
We usually like to recommend the Crystal Quest 1000C or 1000CP (see above). However, in some cases no matter how good an RO system additional pre-treatment of the well water is required. Otherwise the different filter components, and the delicate RO membrane in particular, will clog in no time because the water is simply too heavily laden with hardness minerals, sediment, or iron for example.
This pre-treatment could be a simple sediment filter setup with 3 cartridges rated at 50, 10, and 5 microns to remove dirt, rust, sand, silt, etc. For very hard water, you should consider installing a water softener in your home. With iron contamination, a different type of pre-treatment is required, depending on the iron type and concentrations.
By the way, filtering raw well water with reverse osmosis alone is not a good idea for sure. It could be biologically unsafe and therefore require some sort of disinfection such as shock chlorination.
But this goes beyond the scope of this article. For now, all you need to remember is that well water oftentimes requires a different and more sophisticated approach than municipal water when it comes to the right treatment method(s). What should be your next step? Having your water tested.
How to Remineralize RO Water
Drinking water treatment by means of reverse osmosis filtration removes minerals. If that’s something you are concerned about we want to provide you with some basic information on what you can do to still cover your daily mineral intake with ease.
Let’s take calcium as an example: Only about 20% of our recommended daily intake (RDI) comes from the water we drink. The remaining 80% comes from our food. Nevertheless, if we drink RO purified water instead of bottled water chances are that we may not cover our calcium RDI entirely. The same applies to magnesium. For all other minerals, including iodine, iron and zinc, drinking water provides less than 5% of the RDI.
The Solution: Reverse Osmosis Filtration System with Remineralization Stage
The most convenient solution for demineralized drinking water is to add a remineralization stage to your reverse osmosis filtration system. During the additional treatment step, beneficial minerals are released in the water. It doesn’t get any easier!
Another option is to use an electrolyte blend. The main focus here should be a balanced mineral composition. About 60 ppm calcium and 25 ppm of magnesium are ideal. An alternative to electrolyte blends are green powder blends and mineral-rich salts, e.g. Himalayan salt.
Frequently Asked Questions
Is reverse osmosis water healthy to drink?
There are two aspects to this question. From a water quality perspective, reverse osmosis water contains almost no impurities. However, research suggests that, because RO water lacks beneficial minerals, it’s better to remineralize it before consumption. One way you can do this is by mixing in a high quality mineral blend. Remineralization will also improve drinking water taste.
Is reverse osmosis worth the money?
Absolutely! The quality of your water will be great.
What is the pH of reverse osmosis water?
The pH of most RO waters is slightly acidic. That’s because it lacks minerals like calcium and magnesium. We suggest remineralization before use which will raise the pH.
Do I really need a reverse osmosis system?
It depends on the quality of your water source. If it’s bad and you want to protect your family from harmful contaminants, then yes, RO could be worth it.
How much does it cost to install a reverse osmosis system?
Portable systems are installation-free so it costs nothing. As for under sink models, prices start at $150. You can also do this yourself if you’re not afraid to drill a hole in your kitchen counter and drain line. If you decide to hire a plumber make sure to reach out to more than one company so that you can compare estimates.
Questions about reverse osmosis systems? Ask Away!
And make sure to revisit this buying guide from time to time as we are going to continue our hunt for the best reverse osmosis system and add new reverse osmosis system reviews occasionally.
Gene Fitzgerald has been with BOS since the very beginning. She is head of content creation and has fully immersed herself into the home water treatment industry only to become an expert herself. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
Learn more about Gene and the rest of the BOS Team.