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We made the Aquasana Claryum Direct Connect a great choice – it’s easy to install and provides high water flow to existing faucets.
People who drink more than a few gallons of potable water per day are likely to be most satisfied with an under-sink filtration system like the Aquasana AQ-5200.If you prefer (or need) filtered water, this can be supplied continuously from a separate tap as needed.We recommend the Aquasana AQ-5200 because its certification is the best of any system we’ve found.
Certified for most contaminants, widely available, affordable, and compact, the Aquasana AQ-5200 is the first under-sink water filtration system we look for.
Aquasana AQ-5200 is ANSI/NSF certified to eliminate nearly 77 different contaminants, including lead, mercury, volatile organic compounds, pharmaceuticals, and other materials that competitors rarely capture.It is one of the few filters certified by PFOA and PFOS, compounds involved in the manufacture of nonstick materials, that received an EPA health advisory in February 2019.
A set of replacement filters costs about $60, or $120 per year on Aquasana’s recommended six-month replacement cycle.Also, the system is only larger than a few cans of soda and doesn’t take up a lot of valuable space under the sink.This widely used system uses high-quality metal hardware, and its faucets come in a variety of finishes.
The AO Smith AO-US-200 is identical to the Aquasana AQ-5200 in terms of certifications, specifications and dimensions, and is exclusive to Lowe’s, so it is not as widely available.
The AO Smith AO-US-200 is identical to the Aquasana AQ-5200 in every important respect.(That’s because AO Smith bought Aquasana in 2016.) It has the same premium certification, all-metal hardware, and compact form factor, but isn’t as widespread because it’s only sold at Lowe’s, and its faucet only comes in one finish Treatment: Brushed Nickel.If that suits your style, we recommend shopping between the two models by price: one or the other is often discounted.Filter replacement costs are similar: about $60 for a set, or $120 per year for a six-month cycle suggested by AO Smith.
The AQ-5300+ has the same excellent certifications but with higher flow and filtration capacity for homes that use a lot of water, but costs more and takes up more space under the sink.
The Aquasana AQ-5300+ Max Flow has the same 77 ANSI/NSF certifications as our other top picks, but offers higher flow (0.72 vs. 0.5 gallons per minute) and filtration capacity (800 vs. 500 gallons).This makes it an option for households who need a lot of filtered water and want to get it as quickly as possible.It also adds a sediment pre-filter, which the AQ-5200 doesn’t have.This may prolong the higher flow of pollutant filters in homes with sediment-rich water.That said, the AQ-5300+ model (with a 3-liter bottle filter) is significantly larger than the AQ-5200 and AO Smith AO-US-200, but has the same recommended filter life of 6 months.And its upfront cost and filter replacement cost is higher (about $80 per set or $160 per year).So weigh its benefits against the higher cost.
The Claryum Direct Connect installs without drilling holes and delivers up to 1.5 gallons of filtered water per minute through your existing faucet.
Aquasana’s Claryum Direct Connect connects directly to your existing faucet, making it an especially attractive option for renters (who may be barred from changing their location) and those who cannot install a separate filter faucet.It doesn’t even have to be mounted on the sink cabinet wall – it can simply lie on its side.It offers the same 77 ANSI/NSF certifications as our other Aquasana and AO Smith options, and delivers up to 1.5 gallons of filtered water per minute, more than others.The filter has a rated capacity of 784 gallons, or approximately six months of use.But it doesn’t have a sediment pre-filter, so if you have sediment problems, it’s not a good choice as it will clog.And it’s huge — 20½ x 4½ inches — so if your sink cabinet is small or crowded, it probably won’t fit.
Certified for most contaminants, widely available, affordable, and compact, the Aquasana AQ-5200 is the first under-sink water filtration system we look for.
The AO Smith AO-US-200 is identical to the Aquasana AQ-5200 in terms of certifications, specifications and dimensions, and is exclusive to Lowe’s, so it is not as widely available.
The AQ-5300+ has the same great certifications but with higher flow and filtration capacity for homes that use a lot of water, but costs more and takes up more space under the sink.
The Claryum Direct Connect installs without drilling holes and delivers up to 1.5 gallons of filtered water per minute through your existing faucet.
I have been testing water filters for Wirecutter since 2016.In my report, I had lengthy conversations with filter certification organizations to understand how their testing was conducted, and dug into their public databases to confirm that the manufacturer’s claims were supported by Certification test.I also spoke with representatives of several water filter manufacturers, including Aquasana/AO Smith, Filtrete, Brita and Pur, to ask what they had to say.And I’ve experienced all of our options firsthand, because overall livability, durability, and user-friendliness are important for a device you use multiple times a day.Former NOAA scientist John Holecek researched and wrote early Wirecutter water filter guidelines, conducted his own testing, commissioned further independent testing, and taught me a lot of what I know.My work is built on his foundation.
Unfortunately, there is no one-size-fits-all answer to whether you need a water filter.In the United States, public water supplies are regulated by the EPA under the Clean Water Act, and water leaving public water treatment plants must meet strict quality standards.But not all potential pollutants are regulated.Likewise, contaminants can seep into the water after leaving the treatment plant through leakage pipes (PDF) or through the pipes themselves.Water treatment at the plant (or neglected) can exacerbate leaching in downstream pipelines—as happened in Flint, Michigan.
To find out exactly what’s in your supplier’s water when it leaves the facility, you can usually look up your local supplier’s EPA-mandated consumer confidence report online; if not, all public water suppliers are required to provide you with a CCR on request.But due to potential downstream contamination, the only way to be sure of the water in your home is to pay a local water quality lab to have it tested.
As a rule of thumb: the older your home or community, the greater the risk of downstream contamination.The EPA says that “homes built before 1986 are more likely to use lead pipes, fixtures and solder”—old materials that were once commonplace and do not meet current codes.Age also increases the likelihood of pre-regulated industry legacy groundwater contamination, which can be a risk, especially when combined with age-related degradation of underground pipes.
If your household drinks more than two to three gallons of potable water per day, an under-sink water filter may be a better option than a jug filter.The under-sink system provides filtered drinking water on demand without waiting for the filtration process to complete, just like a water tank.Filtration “on demand” also means that the under-sink system can provide enough water for cooking — for example, you can fill a pot with filtered water to cook pasta, but you’ll never repeatedly refill the pitcher for that.
Under-sink filters also tend to have a much longer capacity and lifespan than canister filters—typically hundreds of gallons and six months or more, compared to 40 gallons and 40 gallons for most canister filters. two months.And because under-sink filters use water pressure rather than gravity to push water through the filter, their filters can be denser, so they can remove a wider range of potential contaminants.
On the downside, they are more expensive than pitcher filters, and filter replacements are also more expensive in absolute terms and average over time.The system also takes up space in the sink cabinet that would otherwise be available for storage.
Installing an under-sink filter requires basic plumbing and hardware installation, but it’s a simple job only if your sink already has a single tap hole.If not, you’ll need to knock out one of the built-in faucet locations (visible as raised discs on steel sinks, or marks on synthetic stone sinks).Without a knockout, you’ll need to drill a hole in the sink, and if your sink is undercounter, you’ll also need to drill a hole in the countertop.If you currently have a soap dispenser, dishwasher air gap, or handheld sprayer on the sink, you can remove it and install the faucet there.
These water filters, tanks and dispensers are certified to remove contaminants and improve household drinking water.
This guide is about a specific type of under-sink filter: those that use a cartridge filter and send filtered water to a separate faucet.These are the most popular under-sink filters.They take up little space and are generally easy to install and maintain.They use adsorbent materials—usually activated carbon and ion-exchange resins, like pitcher filters—to bind and neutralize pollutants.We’re not talking about faucet-mounted filters, reverse osmosis systems, or other tanks or dispensers.
To ensure we only recommend filters you can trust, we’ve maintained that our selection is certified to the industry standard: ANSI/NSF.The American National Standards Institute and NSF International are private, not-for-profit organizations that work with the EPA, industry representatives and other experts to develop stringent quality standards and testing protocols for thousands of products, including water filters.The two main accredited laboratories for water filters are NSF International itself and the Water Quality Association (WQA).Both are fully accredited in North America by ANSI and the Standards Council of Canada for ANSI/NSF accreditation testing, and both must adhere to the exact same testing standards and protocols.Filters do not meet certification standards until well beyond their expected lifespan, using prepared “challenge” samples that are far more contaminated than most tap water.
For this guide, we focus on filters that have chlorine, lead, and VOC (aka volatile organic compounds) certifications.
Chlorine certification (according to ANSI/Standard 42) is important because chlorine is often the culprit behind the “bad taste” of tap water.But it’s also pretty much a giveaway: Almost all types of water filters are certified.
Lead certification is difficult to achieve because it means reducing lead-rich solutions by over 99%.
VOC certification is also challenging, as it means the filter can virtually eliminate over 50 organic compounds, including many common biocides and industrial precursors.Not all under-sink filters have both certifications, so by focusing on filters that have both certifications, we’ve identified those that perform significantly better.
We narrowed our search further to select filters certified to the relatively new ANSI/NSF Standard 401, which covers a growing number of emerging contaminants in US waters, such as pharmaceuticals.Also, not all filters have 401 certification, so the ones that have it (as well as lead and VOC certifications) are a very select group.
Within this strict subset, we then look for those with a minimum capacity of 500 gallons.This equates to a filter life of approximately six months with heavy use (2¾ gallons per day).For most households, this is enough filtered water for daily drinking and cooking.(Manufacturers provide recommended filter replacement schedules, usually measured in months rather than gallons; we follow these recommendations in our evaluations and costing calculations. We recommend always using original manufacturer replacements, not third-party filters.)
Finally, we weighed the upfront cost of the entire system against the ongoing cost of replacing the filter.We didn’t set a price floor or ceiling, but our research showed that while up-front costs ranged from $100 to $1,250 and filter costs from $60 to nearly $300, these differences were not reflected in the clearly superior A more expensive model in specs.We’ve found several under-sink filters for well under $200 while offering excellent certification and longevity.These became our finalists.In addition to this, we also look for:
During our research, we occasionally came across reports of catastrophic leaks from under-sink water filter owners.Since the filter is attached to the cold water inlet line, if the connector or hose breaks, water will flow out until the shut-off valve closes – meaning it could take hours or even days for you to discover the problem, with serious consequences for your water damage .This is uncommon, but there are risks to weigh when considering purchasing an under-sink filter.If you do buy one, follow the installation instructions carefully, taking care not to push the connector through, then slowly turn on the water to check for leaks.
A reverse osmosis or R/O filter starts with the same type of cartridge filter we’ve chosen here, but adds a secondary reverse osmosis filtration mechanism: a fine-pored membrane that allows water to pass through but filters out dissolved minerals matter and other substances.
We may discuss R/O filters in depth in a future guide.Here we categorically reject them.They have limited functional advantages over adsorption filters; they produce a lot of wastewater (usually filtering 4 gallons of wasted “flush” water per gallon), while adsorption filters do not produce any wastewater; they take up more space , because unlike adsorption filters, they use a 1 or 2 gallon tank to store filtered water; they are much slower than under-sink adsorption filters.
We have conducted laboratory tests on water filters over the past few years, and our main takeaway from our testing is that ANSI/NSF certification is a reliable measure of filter performance.This is not surprising given the extreme rigor of certification testing.Since then, we have relied on ANSI/NSF certification rather than our own limited testing to select our competitors.
In 2018, we tested the popular Big Berkey water filter system, which is not ANSI/NSF certified, but claims to have been extensively tested to ANSI/NSF standards.This experience further cemented our insistence on true ANSI/NSF certification and our distrust of the “ANSI/NSF Tested” claim.
Since then, and in 2019, our testing has focused on real-world usability and the kinds of useful features and drawbacks that become apparent as you use these products.
Certified for most contaminants, widely available, affordable, and compact, the Aquasana AQ-5200 is the first under-sink water filtration system we look for.
Our pick is the Aquasana AQ-5200, aka the Aquasana Claryum Dual-Stage.Its most important feature to date is that its filters have the best ANSI/NSF certifications of our competitors, including chlorine, chloramines, lead, mercury, VOCs, multiple “emerging pollutants” and PFOA and PFOS .Other than that, its faucet and plumbing hardware is made of solid metal, which is superior to the plastic used by some other manufacturers.And the system is also very compact.Lastly, the Aquasana AQ-5200 is one of the best values ​​we’ve found in under-sink filters, the upfront cost of the entire system (filter, housing, faucet, and hardware) is typically around $140 upfront, and a set of two is priced at $60 to replace the filter.That’s less than many competitors with weaker certifications.
The Aquasana AQ-5200 is ANSI/NSF certified (PDF) to detect 77 contaminants.Along with the similarly certified Aquasana AQ-5300+ and AO Smith AO-US-200, this makes the AQ-5200 the strongest certified system of our choice.(AO Smith acquired Aquasana in 2016 and adopted most of its technology; AO Smith has no plans to phase out the Aquasana product line.) In contrast, the excellent Pur Pitcher filter with lead reduction has a 23 certification.
These certifications include chlorine, which is used to kill pathogens in municipal water supplies and is the leading cause of “bad taste” in tap water; lead, which leaches from old pipes and plumbing solder; mercury; live Cryptosporidium and Giardia flagellates, two potential pathogens; and chloramine, a persistent chloramine disinfectant increasingly used by filter plants in the southern United States, pure chlorine that degrades rapidly in warm water.Aquasana AQ-5200 is also certified for a growing number of 15 “emerging contaminants” in public water systems, including BPA, ibuprofen, and estrone (an estrogen used in birth control); for PFOA and PFOS— — Fluorine-based compounds used to make nonstick substances and received an EPA health advisory in February 2019.(At the time of consultation, only 3 manufacturers of such filters were PFOA/S certified, making this particularly noteworthy.) It is also VOC certified.This means it can effectively remove over 50 different organic compounds, including many pesticides and industrial precursors.
In addition to activated carbon and ion exchange resins (common if not all under-sink filters), Aquasana uses two additional filter technologies to achieve certification.For chloramines, it adds catalytic carbon, a porous and therefore more reactive activated carbon produced by treating the carbon with a high temperature gas.For Cryptosporidium and Giardia, Aquasana makes the filter by reducing the pore size to 0.5 microns, small enough to physically trap them.
The superior certification of the Aquasana AQ-5200 filter was the main reason we chose it.But its design and materials also set it apart.The faucet is made of solid metal, as are the T-clamps that connect the filter to the pipe.Some competitors use plastic for one or both, reducing costs but increasing the risk of cross-threading and incorrect installation.The AQ-5200 uses compression fittings to ensure a tight, secure seal between the tubing and the plastic tubing that carries water to the filter and faucet; some competitors use simple push-on fittings, which are less secure.The AQ-5200 faucet is available in three finishes (brushed nickel, polished chrome, and oiled bronze), while some competitors have no choice.
We also like the compact form of the AQ-5200 system.It uses a pair of filters, each a bit larger than a soda can; some others, including the Aquasana AQ-5300+ below, are the size of a liter bottle.With the filter installed on the mounting bracket, the AQ-5200 measures 9 inches high, 8 inches wide, and 4 inches deep; the Aquasana AQ-5300+ measures 13 x 12 x 4 inches.This means the AQ-5200 takes up significantly less space in a sink cabinet, can be installed in tight spaces where larger systems can’t fit, and leaves more room for under-sink storage.You need about 11 inches of vertical space (measured down from the top of the enclosure) to allow for filter replacement, and about 9 inches of unobstructed horizontal space along the cabinet wall to install the enclosure.
The AQ-5200 is rated very well for water filters, earning 4.5 out of 5 out of 800 reviews on Aquasana’s website and 4.5 out of nearly 500 reviews at Home Depot.
Lastly, the current price of a complete system for the Aquasana AQ-5200 is about $140 (often sold for close to $100) and $60 for a set of replacement filters ($120 per year for a 6-month replacement cycle), the Aquasana AQ-5200 It’s one of the best values ​​among our competitors and is hundreds of dollars cheaper than some models with less extensive certifications.The unit includes a timer that will start beeping when you need to change the filter, but we recommend setting a recurring calendar reminder on your phone.(You’re unlikely to miss it.)
Compared to some competitors, the Aquasana AQ-5200 has a lower maximum flow (0.5 gpm vs. 0.72 or more) and lower capacity (500 gallons vs. 750 or more).This is a direct result of its physically smaller filter.Overall, we think these minor shortcomings are outweighed by its compactness.If you know you need higher flow and capacity, the Aquasana AQ-5300+ is rated at 0.72 gpm and 800 gallons, but with the same six-month filter replacement schedule, the Aquasana Clarium Direct Connect offers ratings up to 1.5 gpm Flow to 784 gallons and six months.