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11 Best Reverse Osmosis Systems of 2021 – Reviews and Buying Guide

If you want pure, clear water at home you can’t do better than a reverse osmosis system. 

Well, unless you want to ship in extremely expensive mineral water daily of course!

I’m going to assume you don’t. 

So, let’s talk about reverse osmosis...

Why do you need a reverse osmosis system?

Reverse osmosis works by forcing water through a membrane at pressure. That membrane is so incredibly fine that only water molecules can get through, leaving behind all nasties and contaminants. 

That means when you use a reverse osmosis filter, you’re getting probably the closest thing to genuinely pure water you ever will.

Impressive, right?

So, what are the best reverse osmosis systems on the market right now?

1. Home Master TMAFC-ERP - Best of the Best

The Home Master TMAFC-ERP is designed with solving the problems of most reverse osmosis systems in mind. It’s the reverse osmosis filter system for people who are sceptical of reverse osmosis filter systems.

Home Master TMAFC-ERP

Pros

  • Built to solve many RO issues
  • Easy to install and maintain
  • Removes 98% of contaminants
  • Includes faucet

Cons

  • This is quite a pricy system, but it is worth it
  • You will need space beneath your main kitchen sink in order to install the TMAFC-ERP

What does the Home Master do differently? Well, first of all this under sink, tank RO system adds calcium and magnesium to your water twice during the filtration process to make sure that you’re drinking enriched water. 

Secondly, the Fast Flo RO kit means that flow rates are not made sluggish by a Home Master filtration system. 

Finally, the built in non-electric pump reduces water waste by an amazing 80%, so your water bills won’t cost the Earth and nor will you damage the Earth by using insane amounts of H2O.

On top of all that, all the components used in the TMAFC-ERP are individually BSF certified (an unusual mark of quality for a reverse osmosis system like this one), and the system’s modular design make it extremely easy to upgrade and service. Filters should be changed around every 2000 gallons (roughly once a year), and no tools are required to do so.

In all, the Home Master offers seven stages of filtration and mineralisation, and removes an incredible 98% of contaminants from your water supply. It truly is an incredible filter system, providing access to fast flowing, crystal clear mineral water at the touch of a faucet.

Bottom Line

If you have been thinking about a reverse osmosis system, but were worried about some of the classic issues with RO filters, then worry no more! The Home Master TMACF-ERP has pretty much solved them.


2. APEC Water Systems ROES-50 - Best for Drinking Water

This is an RO system from America’s no. 1 rated water filter brand, so you know it’s going to be quality.

APEC Water Systems ROES-50

Pros

  • A very affordable system
  • Comes with everything needed for installation
  • Excellent 5-stage filtration removes an amazing 99% of contaminants

Cons

  • Should be professionally installed
  • No remineralisation, though some consumers prefer this

The APEC ROES-50 offers exceptional, US-designed quality and a seal of approval from the WQA, who have certified the system. Offering a water pressure of 40-85 psi, this system won’t slow down flow in your kitchen, and it can be installed under pretty much any sink as long as there is room for the tank.

The APEC comes with a faucet, along with all the tubing and adaptors needed for installation, but should be installed by a professional if you don’t personally have decent plumbing skills. Fittings are high quality and leak free, and the faucet is stainless steel (no heavy metals are used in its production).

With a 2-year warranty as standard, you can trust that this five-stage filtration system is built to last. It includes two carbon block filters and a coconut carbon filter on top of the reverse osmosis filter and sediment filters you would expect to find as a minimum in a system like this.

The APEC is really affordable for such a high quality system, and as it doesn’t remineralise water you don’t need to worry about changing additional cartridges or sourcing them. 

Bottom Line

If you want an easy to use RO system at a great price, and don’t feel comfortable with remineralised water, then give the APEC ROES-50 a try.


3. iSpring RCC7AK 6-Stage - Best Under Sink

The iSpring RCC7AK 6-Stage is a great value, NSF certified reverse osmosis filter for undersink use. iSpring are a hugely trusted water filter provider, with loads of experience of providing at-home water filtration solutions.

iSpring RCC7AK 6-Stage

Pros

  • This is an excellent value system
  • All installation materials are included, as well as very clear instructions
  • NSF 58 certified
  • Excellent, US-based support
  • The remineralization and alkalisation stage is an unusual addition

Cons

  • If alkalised water isn’t something you’re interested in, skip the iSpring
  • This RO filter system does produce a fair amount of wastewater

On top of the three pre-filters, a PP sediment filter, a carbon KDF (GAC) filter, and a carbon block (CTO) filter, and the all-important RO filter, the RCC7AK offers a final KDF filter and then a fantastic remineralization and alkalisation filter which both remineralizes and softens water to ensure the healthiest water possible for you and your family at the touch of a faucet! 

This RO filter, with its NSF/ANSI 58 certification, delivers bottled mineral-water quality water at a fraction of the price of constantly stocking up on bottles.

It comes with a faucet, along with everything needed for installation. Installation videos on the iSpring site mean that if you have some plumbing skills you should be able to install the iSpring RCC7AK yourself, and otherwise it should take a handyman or plumber no time at all.

iSpring also offer some of the best customer support available for a water filter system like this. All of their support staff are US based, working out of GA, and once you register with the company you will receive lifetime support from professionals. 

With some of the longest-lasting filters in the industry, the iSpring is easy to maintain. And of course, you will be supported at all times with all tech issues if you buy an iSpring. That includes any issues you have with filter changes, etc.

Bottom Line

If you’re a little nervous about installing and maintaining an RO filter system under your kitchen sink, and want one of the best value systems out there, then get yourself an iSpring RCC7AK 6-Stage.


4. Waterdrop RO Reverse Osmosis Water Filtration System

This tankless reverse osmosis water filtration system is a big investment, but if you’re working with a smaller space it might be just what you need.

Waterdrop RO Reverse Osmosis Water Filtration System

Pros

  • Although it’s expensive, the features of the Waterdrop mean it’s good value
  • Space saving
  • Incredibly easy to install and maintain, helped along by the filter status light and composite filter
  • Comes with everything needed for installation

Cons

  • This is a big-ticket item, so it’s not a good choice if you’re trying to save the pennies
  • There’s no remineralisation stage with the waterdrop

Not only does the Waterdrop’s tankless design save space, it also means that installation is easy and fuss free. This filter should only take about thirty minutes to install - that’s an awful lot quicker than a traditional undersink RO filter with a tank, which can take a couple hours to install if you aren’t an expert. 

And that’s not where the ease of use stops, not by any means! A composite filter combines all the filters you would expect, including PP, activated carbon and of course RO, into one. This means that changing the filter takes about thirty seconds. And you know just when to change the filter (and when to order a new one, too) because the included faucet has a state of the art filter indicator light in its base.

The Waterdrop comes with three filters included, so you won’t need to order more for a while anyway!

This filter is working hard 24 hours a day, with an auto-flushing system and a reminder for shut-off. Essentially, you won’t find any other RO filter that is easier to use, more intuitive, or more convenient.

Bottom Line

If comfort, style and ease of use are more important to you at the moment than finding the cheapest possible product, then the Waterdrop is undoubtedly the RO filter for you.


5. Express Water RO5DX - Best Budget Pick

This undersink reverse osmosis filter system from Express Water is a fantastic budget option for anyone who wants clean, clear water they can trust without breaking the bank.

Express Water RO5DX

Pros

  • Amazing value
  • Five-stage filtration deals with 99% of contaminants
  • Easy to install and maintain, with much of the system coming pre-assembled

Cons

  • This system has no remineralisation stage
  • It produces a fair amount of wastewater

The Express RO5DX consists of a sediment filter, a granular filter, as well as a reverse osmosis filter and a coconut carbon post-filter to ensure the purest water possible every time you turn on the faucet.

And speaking of the faucet, it comes with a stainless steel faucet along with everything else you need to set up your new undersink RO filter system with a tank. And set-up is exceptionally easy with the RO5DX, with 50% more pre-assembly as standard than most of its competitors.

Like all Express Water RO systems, the RO5DX comes with a no-questions asked 1-year warranty. It shouldn’t be needed though, because upkeep is as easy as installation with the RO5DX. Prefilters should be replaced every six months, while RO filters last around a year. A quick color-match system makes this all really simple.

This system doesn’t include any remineralisation, and the tank system does use a fare amount of water, but there is nothing comparable at the price point. 

Bottom Line

The Express Water RO5DX is the perfect starter RO system, and a budget option anyone with one eye on their wallet should consider.


6. iSpring RCC7AK-UV - Best for Well Water

The iSpring RCC7AK-UV includes all the features of the excellent RCC7AK, but with an additional UV post-filter.

iSpring RCC7AK-UV

Pros

  • Includes a remineralisation and alkalisation stage
  • Easy to install and maintain
  • Can be used on both lake and well water, as well as water from a municipal supply

Cons

  • This is quite an expensive option
  • Unless you’re relying on lake or well water, you might want to consider the cheaper version without the UV filter

It’s a slightly more expensive option, but the UV filter element means that all bacteria and viruses are eliminated with no use of chemicals or potential contaminants. When combined with the existing combination of sediment, carbon and RO filters that characterise the RCC7AK you get an unrivaled purity of water coming out of your faucet.

The iSpring RCC7AK-UV can deal not only with poor municipal water supplies, but also both well water and lakewater. That means that wherever you live, and whatever your water source, this RO filter will work for you.

The system comes with everything you need to set it up, and when installed correctly (DIY if you have any plumbing knowledge, or by a handyman or plumber otherwise) it should maintain a pressure of 45-70psi.

Bottom Line

If you want an RO filter that does everything, including a UV stage, then choose the iSpring RCC7AK-UV.


7. APEC Water Systems RO-CTOP-C Portable - Best Countertop

The APEC is a really incredible bit of kit. It’s a portable, tankless RO water filter system that comes at an incredibly reasonable price - not something you see every day by any means.

APEC Water Systems RO-CTOP-C

Pros

  • An amazing portable RO system, unlike almost all competitors
  • Four stages of filtration
  • Purifies up to 90 gallons of water per day

Cons

  • This is a portable system, it won’t handle the needs of a whole family day to day
  • There’s no remineralization process

This lightweight and practically instillation-free system plugs into almost all faucets in minutes, and with its case it can be transported almost anywhere with ease (it should be noted that the RO-CTOP-C does not fit pull out faucets). 

This four-stage system can purify up to 90 gallons of water per day, maintaining up to 60psi of water pressure. All the filters are US made and high capacity, and they are as follows: five micron sediment filter, coconut carbon filter, TFC reverse osmosis membrane, and a final coconut carbon filter to remove any unpleasant tastes

As it’s so small, light and portable, the APEC does not include remineralisation, but it would be pretty shocking if it did given its price point and design. 

Bottom Line

Whether you’re worried about drinking the tap water in a holiday home, or particularly sensitive to a particular contaminant, the APEC RO-CTOP-C is the logical choice for a portable RO system.


8. Express Water UV

Another excellent, UV-enabled reverse osmosis system, the Express water impresses with an incredible eleven stages!

Express Water UV

Pros

  • A great system with an amazing number of stages
  • UV filter gets rid of all bacteria and viruses
  • An excellent remineralization and alkalization stage
  • Easy to put together and maintain

Cons

  • This system does produce a fair amount of wastewater
  • The 11 stages mean there are a lot of cartridges to keep track of and change

As you would hope with such a complex system, the Express promises to remove up to 99.9% of heavy metals and other contaminants from your drinking water. It consists of active block carbon, active granulated carbon, RO, and sediment filters, plus the aforementioned UV filter, a post-carbon filter and remineralization and alkalization stage.

What does all this mean? 

Well, basically it means that you get mineral-water quality H2O straight out of your faucet!

The Express Water UV is designed to be quick to install and easy to understand, meaning that both the bi-annual filter changes and initial installation should be easy, even for novices. 

Its quick-connect system is color coded, and labeled for ease of use. On top of that, a leak detection system means you never have to worry about unnoticed cracks or leaks within your undersink RO filtration system.

Bottom Line

If you’re looking for a balance of value and performance, you should definitely consider the Express Water UV.


9. AlcaPure Reverse Osmosis Countertop - Best Apartment

As a countertop water filter, the AlcaPure is an incredibly easy way to run a reverse osmosis system (which, as we all know, can be a hassle).

AlcaPure Reverse Osmosis Countertop Water Filter

Pros

  • Incredibly easy to install and move
  • Small footprint
  • Four-stage filtration system

Cons

  • A 1:1 ratio of purified to waste water
  • You have to remember to fill this filter, so perhaps it’s not the best choice for large, busy families

In fact, there is no installation required whatsoever with the AlcaPure. You just assemble the countertop filter, fill it, and run it. It’s designed to be compact, with a small, square footprint, so it fits in smaller kitchens and even in RVs.

The countertop filter includes four stages, with a sediment filter, an active carbon filter, an RO filter, and a post-filter for absolute purity. The filter warns you when cartridges need changing, so you can always stay on top of the (minimal) maintenance needed. This should only be about every 12 months, so don’t worry about excessive maintenance needs!

The Alcapure will provide you with 0.5 gallons of purified water in about 15 minutes when you fill it with a gallon of tap water. The rest is wastewater, so you will have to get rid of it.

Bottom Line

If you’re looking for a countertop filter to fill and forget about, look no further than the AlcaPure.


10. Brondell Circle Reverse Osmosis System

The biggest joy of the Brondell is its efficiency. It’s up to 10 times more efficient than many competitors, which is pretty incredible.

Brondell Circle Reverse Osmosis System

Pros

  • No-electricity is needed for this RO system
  • Comes with a faucet, ready for easy installation
  • Includes a filter change light
  • Efficient four-stage system

Cons

  • No remineralization system
  • This is an expensive system, comparatively, but it’s also stylish, space saving, and easy to install

On top of that, the Circle’s 6 liter tank refills in under an hour so it is constantly working hard to purify water for you and your family. It’s designed to react to your water use, meaning that it never wastes more water than absolutely necessary for optimal purification.

The four filtration stages of the Brondell Circle are a sediment filter, an activated carbon filter, an RO membrane filter (of course) and a carbon block post filter. All this adds up to clean, clear, purified water on tap!

Speaking of which, the Brondell comes with a stylish faucet ready for installation. And it includes an LED filter change reminder light so that you’ll always know when you need to work on upkeep for your reverse osmosis system.

This is a no electricity system, so it’s easy to install and works pretty much anywhere! Of course, as it is so compact this system does not include a remineralization stage.

Bottom Line

If you’re looking for an incredible, modern RO system, and don’t care about paying a bit of a premium for it, get yourself a Brondell Circle Reverse Osmosis Under Sink.


11. Waterdrop Tankless Reverse Osmosis System - Best Tankless

This is a fantastic value tankless RO system, and like all tankless systems it saves both space and installation hassle.

Waterdrop Tankless Reverse Osmosis System

Pros

  • Incredible value for a tankless under sink system
  • Space saving
  • Very little upkeep and installation

Cons

  • A 1:1 waste to purification ratio isn’t amazing
  • There’s no remineralization component, but you wouldn’t expect one at this price on an under sink unit

The Waterdrop tankless isn’t as elegant as some tankless systems, and it has a 1:1 wastewater to purified water ratio, but it really is amazing value for money.

The filter within the Waterdrop is composite, meaning less upkeep (only one filter to change). It does, however, contain three stages in a compact space, including a sediment PP membrane and an activated carbon block on top of the RO filter.

The small system means you’re saving an amazing 70% space wise when compared to comparable systems with tanks. So, if you’re dealing with an apartment or a small space beneath your sink, it makes a huge amount of sense to consider this set up.

Bottom Line

If you want a great value RO system, but space is at a premium, then definitely consider the Waterdrop London Tankless Reverse Osmosis System.


Is Drinking Reverse Osmosis Water Safe and Healthy?

Whilst water that has been filtered using reverse osmosis is some of the purest water in the world, there is a legitimate argument that it might be too pure. 

That’s because reverse osmosis membranes are so fine they allow only water molecules to pass through, filtering out even minerals. Normal tap water contains magnesium, calcium and sodium at levels that can help you get your RDA of these minerals. 

Magnesium, calcium and sodium are all useful for normal nerve and muscle function, so removing a main source of them from your diet can be dangerous!

To counter this, you can remineralise water once it has been filtered. However, the remineralisation packs are not particularly well regulated, and synthetically manufactured minerals aren’t as good for you as the natural variety. For that reason, you may want to think hard about an RO system if it’s going to filter all of your drinking water.

Reverse Osmosis Pros and Cons

Reverse osmosis has some cons, and of course many pros.

Cons include: 

  • Water being stripped of minerals, so there is a danger of not getting your RDA of things like calcium and magnesium
  • A fair amount of upkeep, particularly changing cartridges in systems with many stages
  • Wastewater is inevitable in a reverse osmosis system, which has an affect on both your water bills and the environment
  • They can be somewhat tough to install alone if you don’t have any plumbing knowledge

And yet, many people believe the pros outweigh them:

  • The purest water you can get with an at-home water purification system
  • RO filters remove heavy metals, including lead, which is rare in an at-home filter system
  • Over time, RO systems save money when compared to buying bottled water
  • The issue with minerals can be solved with a remineralization system, which is included in plenty of models of RO system

Types of RO System

There are several types of RO filter on the market, though some are more popular than others. They include:

1. Countertop

These are small filter systems that are often portable. They tend to be either installation free (so, need to be filled regularly) or very easy to install by simply hooking them up to the faucet. 

Countertop filters are suitable for travel, RVs, or smaller families and residences. They tend to consist of three or four filtration stages, including sediment and carbon filters as well as and RO filter.

2. Undersink

Standard undersink RO filters hook up to the cold water line, and include a storage tank and several filter cartridges. Many also include their own faucet, which has to be installed. 

Under sink RO filters can consist of up to nine stages of filtration, including activated carbon, KDF, sediment, and of course RO. 

3. Tankless

These are very like regular under sink filters, but as they don’t have tanks they often can’t process as much water as quickly as a standard under sink system. They are, however, a fantastic option for smaller spaces like apartments.

Final Thoughts

As reverse osmosis filters are so varied and complex, you have to think really carefully about what you want from a new RO system.

If you have a large family (especially if you live with children or older people who have to be careful about getting enough minerals) then you will want to go for something with all the bells and whistles, including remineralization and potentially UV filtration too. For that, I would advise the iSpring RCC7AK-UV. 

The Apec Portable Countertop is an absolutely incredible product, though it is built for travel it could also be used in a smaller home or in general life by a single person or couple. It’s amazingly easy to use, which is a real plus-point, and also a great choice if you need an RO filter for RV trips or similar. 

Finally, the Waterdrop Tankless is amazing value for a compact system that does the job, is easy to install and use, and takes very little upkeep. It would be my choice for a small space if it was more than just me, or me and a partner. It’s also a wonderful budget option if that’s a serious concern.

RO filters can be a slightly contentious issue, and you should consider water usage and your mineral intake needs, but overall every filter on this list is capable of providing incredibly pure water with ease. 


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