Review: Brondell H2O+ Circle Reverse Osmosis Water Filtration System

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In this review, you will learn all you need to know about the Brondell H2O+ Circle Reverse Osmosis Water Filtration System.

Brondell H2O+ Circle Reverse Osmosis Water Filtration System

Brondell H2O+ Circle Reverse Osmosis Water Filtration System

Price: $$$
Filter Stages: 4
Water Flow: 0.07 Gallons Per Minute
NSF Certifications: 42, 53, 58, 372
Annual Cost: ~$190

Overall Rating: 4.0/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

Brondell H2O+ Circle Reverse Osmosis Water Filtration System – All Specs

  • Model: RC100
  • Annual Maintenance Cost: ~$190
  • Filter Media/Process: Sediment Filtration, Activated Carbon, RO
  • Filter Stages: 4
  • Flow Rate: 0.07 gpm
  • Membrane Rating: 100 gpd
  • Recovery Rate: 30.6%
  • Filtering Capacity: 6 Months to 2 Years
  • WxHxD: 9.25″x16.5″x13.8″
  • Weight: 14.6 lb.
  • Water Temperature: 41-95 °F
  • Water Pressure: 40-120 psi
  • Fitting: 3/8”-1/2″
  • NSF Certifications: Standard 42, 53, 58, 372
  • Warranty: 1-Year

Brondell H2O+ Circle – Key Features

The Brondell H2O+ Circle Reverse Osmosis Water Filtration System, or just Brondell Circle, is an under-the-sink unit. Tank and filter stages are integrated into a single, sleek case which saves space. Plus, we like the looks!

However, don’t make the mistake and confuse the Brondell H2O+ Circle with one of the more modern systems that use internal pumps to boost filtration speed and reduce wastewater. The Brondell may look like one of those, but it isn’t. It’s really just a standard under sink unit with a pressurized tank (1.6 gallons) combined into a single case.

With that out of the way, we have 4 filter stages:

  1. Stage 1: A sediment pre-filter reduces larger particulates like sand and rust. This helps to protect subsequent filters from clogging, which extends their lifetime.
  2. Stage 2: The carbon pre-filter reduces chlorine for improved water taste, a long list of potentially harmful VOCs (volatile organic compounds), and organics in general.
  3. Stage 3: The semipermeable RO membrane separates H2O molecules from the majority of nasty contaminants that might be lurking in your water. Example reduction rates are as follows: Lead (98.2%), arsenic(V) (98.9%), chromium 6 (97.3%), fluoride (93.8%), TDS (92.5%).
  4. Stage 4: The carbon block post-filter gives the water a finishing touch improving overall water aesthetics.

As you can see, reduction rates are good, although we’ve seen higher ones (more on this below). You can expect your drinking water to become much safer and healthier, and also better-tasting.

By the way, manufacturer warranty is 1 year.

Filter life: 6 months to 2 years at around $190 in annual cost.

Brondell Circle Reverse Osmosis Pros

There are 3 aspects about the Brondell H2O+ Circle that we’d like to point out:

  1. Compact design – The Brondell H2O+ Circle is sleek and compact. It’s a single elegant box that leaves plenty of room for other household items in the storage cabinet under your kitchen sink.
  2. NSF Compliance – The whole system is tested and certified against NSF Standards 42, 53, 58 and 372. These certifications back up the manufacturer’s claims regarding contaminant reduction and guarantee much safer drinking water for you and your family.
  3. Water saving – Using a circular reservoir, Brondell could eliminate the high backpressure present in every RO system that’s caused by an almost full storage tank. This backpressure is the reason why conventional systems become less efficient and produce substantially more wastewater the more water is inside the tank. With the H2O+ Circle, wastewater is reduced to an average of 69.4%. This sounds like a lot and it is, but 70% wastewater is actually really good for an under sink reverse osmosis system without a pressure pump.

Also worth mentioning is the relatively easy installation. Plus, changing filters doesn’t require tools. In fact, you simply twist the filter elements on/off when installing/removing. Did we mention the chrome faucet with its built-in LED filter-change indicator?

What Contaminants Are Being Removed?

The Brondell Circle has been thoroughly tested and certified against NSF standards. Here are some of the reduction rates, as per the manufacturer:

  • Arsenic 5: 98.9%
  • Cadmium: 98.2%
  • Chromium-6: 97.3%
  • Lead: 98.2%
  • Fluoride: 93.8%
  • TDS: 92.5%
  • Chlorine: 98.4%
  • Various VOCs: 99.8%
  • Cyst: 99.96%

Brondell H2O+ Circle Reverse Osmosis Water Filtration System

The Brondell H2O+ Circle – learn more on


Many of today’s RO systems are bulky. They take up quite some space under your kitchen sink or in the basement and require more effort to install than most other types of water filters. The Brondell H2O+ Circle is not much different – at least as far as installation goes.

You have to drill a hole in your sink or countertop for the extra faucet. You have to install the feed water valve. And you have to connect the wastewater line to the drain. They are not overly complicated, but if you don’t feel comfortable doing these tasks, then you better call a plumber. By the way, all the bits and pieces are contained in the package, including illustrated installation instructions. Here’s a quick rundown of the process:

Please consider these instructions as a general guideline. Always make sure to check and follow your user manual before getting started.
  1. You will need a faucet hole at least 7/16 inches in diameter – if you don’t have one, you’ll need to drill one through your countertop.
  2. Take the faucet out of the packaging.
  3. Insert the top spout into the main body by pushing down until it can’t go any further.
  4. Screw the top cap clockwise until it’s secured in place.
  5. Cut the zip tie on the blue water connection tubing, and unroll it to straighten the tubing. Pay attention to the tubing and make sure to avoid cutting it.
  6. Hook up the escutcheon to the main body – feed the blue tubing through it and push it all the way up.
  7. Install the faucet on top of your countertop or sink, and run the blue tubing through the hole to the cabinet below.
  8. Slide the large plastic washer up through the tubing until it fits snugly against the bottom of the countertop.
  9. Install the lock washer and the locking nut in the same fashion and tighten them until the washer is holding the faucet in place.
  10. Pull the plastic tab from the battery compartment to activate the faucet indicator – the LED should blink red, blue, and then it’s ready.
  11. Turn off your cold water supply and turn on the sink faucet to drain any remaining water.
  12. Disconnect the cold water supply line from the supply valve.
  13. Connect the bottom of the 3/8 inch T-valve to the cold water supply valve at the wall. Use the provided adapters if necessary.
  14. Reconnect the faucet water supply hose to the top of the T-valve, and insert one end of the orange water supply tubing into the T-valve ¼ inch quick connector.
  15. Ensure the T-valve is in the closed position – valve arm facing up.
  16. To connect the quick connectors, simply push the tube into the collet until it can’t go any further.
  17. If you already have a drain connection for the ¼ inch quick connect tube, use that. If not, find a suitable area for the drain clamp.
  18. Drill a ¼ inch hole through one side of the pipe.
  19. Align the drain clamp to the hole – you can use a screwdriver, straw, or a similar thin object for that.
  20. Take out the guiding item and screw the ¼ inch quick connector into place.
  21. Insert the white drain tube into the ¼ inch quick connector and push it firmly into place.
  22. Connect the ¼ inch blue tubing coming from the faucet to the top of the circle, pushing it into the middle hole labeled “Outlet”.
  23. Connect the white tubing to the top of the circle into the hole labeled “Drain”.
  24. Connect the orange tubing to the hole labeled “Inlet”.
  25. Turn on the water and check for leaks.
  26. Turn on the faucet and keep it running for 10 minutes to purge air out of the system.
  27. Turn off the faucet and let the system run for 40 minutes to fill up the tank.
  28. Turn the faucet on and keep it running for 10 minutes.
  29. Turn the faucet off and let the system run for 40 minutes.
  30. Done!


The Package (Parts)

  • RO module with integrated tank (1.6 gallons)
  • 2x pre-filters
  • Post-filter
  • RO membrane
  • Drain clamp
  • Color-coded tubing
  • Chrome faucet with integrated LED filter change indicator
  • Water supply T-valve with rubber washer (⅜” connection)
  • T-valve adapters with rubber washer ⅜” to ½”
  • Filter change chart
  • Manual


Like I said, the Brondell RO system is easy to maintain, thanks to the quick change twist and seal filters. When the LED of the filter change indicator starts to flash red instead of blue, it’s time to change the filters and reset the indicator afterwards by replacing its battery (a new battery comes with each filter replacement set).

Here is what you need to do:

  1. Open the faucet to drain all water from the tank. Leave the faucet open to release any remaining pressure inside the system.
  2. Close the T-valve under your sink to stop water from flowing into the system.
  3. Remove the unit’s front cover.
  4. Remove the filters that need to be replaced by giving them a quarter turn.
  5. Insert the new filters in the same fashion (filter base arrow points to lock).
  6. Replace the front cover.
  7. Turn on the water flow by reopening the T-valve.
  8. Flush the system properly.
  9. Replace the battery in the faucet indicator to reset the timer. After removing the old battery, wait 30 seconds before you insert the new to allow for a full reset.

FYI: The filter change indicator does not measure TDS, but time and water usage. It will start to flash after 6 months or 475 gallons – whichever comes first.

What are the average lifetimes of the filters/membrane?

  • Sediment pre-filter: About every 6 months or 475 gallons
  • Carbon pre-filter: About every 6 months or 475 gallons
  • RO membrane: Every 2 years
  • Carbon post-filter: About every 6 months or 475 gallons

Please be aware that filter life can vary depending on how much water you use on a daily basis and its condition prior to filtration. Water with high levels of hardness minerals/TDS require you to replace the components more frequently.


Here is a link to the official manual:

NSF and Other Certifications

The system comes with NSF certifications 42, 53, 58, and 372.

  • NSF 42: covers aesthetic chlorine, taste and odor.
  • NSF 53: covers VOCs.
  • NSF 58: covers arsenic (V) (50 ppb influent level), barium, cadmium, copper, cyst, fluoride, hexavalent chromium, lead, radium 226/228, selenium, TDS, trivalent chromium.
  • NSF 372: covers structural integrity and material safety.

Earlier Product Versions

To our knowledge, there are no earlier versions of this product.

Brondell Circle Cons

Here is what we don’t like:

  • We heard customers complain about receiving faulty parts that needed replacement before installation.
  • A handful of components are made of cheap plastic or really fragile in general and are likely to break off, such as the handle of the T-valve which allows you to turn the water flow on and off.
  • The system is overall expensive for what it offers – both in terms of the initial purchase and in the long term.
  • With no built-in pressure pump, 7 gallons of water will go down the drain wasted for every 3 gallons filtered.
  • 1.6 gallons of storage should be enough for most family’s but is not a whole lot.

Brondell H2O+ Circle Review: Our Verdict + Best for

We appreciate the thorough NSF certification and testing, as well as the provided contaminant reduction rates. The Brondell Circle Reverse Osmosis Water Filtration System also looks nice and sleek – but the price is, overall, a bit too much for what you get. All in all, it’s still a thumbs up from us. Our verdict: 4 out of 5 stars!

Our Rating in Detail:

  • Filtration Performance: 4.5/5.0
  • Filter Capacity (Life): 5.0/5.0
  • Purchase Price: 3.0/5.0
  • Annual Cost: 4.0/5.0
  • Overall: 4.0/5.0

Comparison to Other Reverse Osmosis Systems

The market offers plenty of alternatives if you’re looking for a good reverse osmosis system – such as the Waterdrop G3 and the AquaTru.

Waterdrop G3 Reverse Osmosis System (G3P600)

Waterdrop G3

Price: $$$
Filter Stages: 4
Flow Rate: 0.42 gpm
NSF: 58, 372
Annually: ~$145

Overall Rating: 4.0/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

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AquaTru Reverse Osmosis Water Filtration System


Price: $$$
Filter Stages: 4
Water: 1 Gallon in 10-15 Minutes
NSF: 42, 53, 58, 401, P473
Annually: ~$100-120

Overall Rating: 4.5/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

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Brondell H2O+ Circle Reverse Osmosis Water Filtration System

Brondell H2O+ Circle

Price: $$$
Filter Stages: 4
Flow Rate: 0.07 gpm
NSF: 42, 53, 58, 372
Annually: ~$190

Overall Rating: 4.0/5.0 ⓘRating based on filtration performance, filter life, price and yearly cost, NSF testing/certification, customer support, product warranty, our testing/experience, user feedback, and other factors.

The Waterdrop G3 is a tankless under sink RO unit which filters water on demand. This makes it very efficient in terms of space utilization. However, it costs a bit more upfront than the Brondell but is far more affordable to maintain (~$145 a year). It comes with 4 filtration stages, with comprehensive NSF testing and one certification backing the contaminant reduction claims. Specifically, the system is tested against NSF standards 42, 53, 58, and 401, and certified for 58. It can cover these contaminants, at the least:

  • VOCs: 99%
  • Chlorine: 99%
  • Nitrate: 98%
  • Fluoride: 99%
  • Arsenic: 99%
  • Chromium-6: 99%
  • Lead: 99%
  • PFOA/PFOS: 99%

The unit uses an internal pump to regulate water pressure, making it very fast (flow rate of 0.42 gallons per minute – you can fill a cup of water in just 8 seconds, almost twice as fast as the Brondell) and water-saving (only 33% of the input water is wasted, as opposed to Brondell’s 70%).

The Waterdrop is pretty easy to install too – and even lets you know when it’s time to replace your filters with the use of LEDs and sound effects. On that note, you can expect between 550 and 2,200 gallons of life out of the different filter stages, meaning they should last you between 6 to 24 months. And when it’s time to replace a filter, doing so is very straightforward without the use of any tools. You can take advantage of the integrated TDS monitoring panel to get an idea of how well your system is operating and what the current state of your water is.

Finally, the system is made of BPA-free materials, and Waterdrop offers a money-back satisfaction guarantee program for the first 30 days after your purchase. You also get 1 year of warranty on top of that – but keep in mind that it’s only valid for systems hooked up to municipal water.

The AquaTru is another great choice if you’re looking for an integrated reverse osmosis system – this one is a countertop model (installation-free) and not an under sink one though. It uses a 4-stage filtration process certified against multiple NSF standards – 42, 53, 58, 401, and P473 – which is quite impressive and gives us a lot of reassurance about the overall performance and quality of the product. Some of the contaminants it can target include:

  • Chlorine: 96.6%
  • VOCs: 95% – 99%+
  • Chromium-6: 97.2%
  • TDS: 87.1%
  • Cyst: 99.99%
  • Fluoride: 93.5%
  • Lead: 99.1%
  • Radium 226/228: 96.4%
  • BPA: 99%
  • Several trace pharmaceuticals and pesticides: 86.7% – 96.6%
  • PFOA, PFOS: 97.5%

Like the Waterdrop G3, the AquaTru utilizes a compact, space-saving design, and is very easy to set up and maintain. It also filters water very fast, and only wastes around 20% of the feedwater – better than both the Brondell and the Waterdrop G3, mainly thanks to the internal pump. The model uses only BPA and BPS-free Tritan plastic in its construction. The only downside is that it can occasionally leak – some users also report units failing prematurely, but we can’t tell if this is a more general trend or just a few isolated incidents (it never happened to us).

Bottom line: The AquaTru is our favorite because it offers a mix of acceptable price, affordable maintenance, NSF-backed filtration, installation-free setup, and fast filtration with little wastewater. Second place is the Waterdrop because it too is effective, tankless + fast, quite easy to install, and water-saving. Compared to that we find the Brondell too expensive. It costs about the same as the other 2 but you don’t get a pump, wastewater is quite high, the system is rather slow. What is really good is the NSF certifications.

This completes our review of the Brondell H2O+ Circle Reverse Osmosis Water Filtration System. If you have any questions please don’t hesitate to leave a comment below!

About the Author Alexandra Uta

Alex is a content writer with an affinity for research and a methodical attention to detail. Since 2020, she has fully immersed herself into the home water treatment industry only to become an expert herself. Alex has been using water filters and similar products for years which has gained her lots of hands-on experience.
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