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We also made Aquasana Claryum Direct Connect a good choice-it is easy to install and can provide high water flow to existing faucets.
Anyone who drinks more than a few gallons of drinking water a day may like to use an under-tank filtration system like Aquasana AQ-5200. If you prefer (or need) filtered water, this can be supplied continuously from a separate faucet as needed. We recommend Aquasana AQ-5200 because its certification is the best of all the systems we have found.
Aquasana AQ-5200 has obtained the most pollutant certification, is widely available, is reasonably priced, and has a compact structure. It is the first under-tank water filtration system we are looking for.
Aquasana AQ-5200 has passed ANSI/NSF certification and can eliminate almost 77 different pollutants, including lead, mercury, volatile organic compounds, drugs, and other materials that are rarely captured by competitors. It is one of the very few filters certified for PFOA and PFOS. These compounds are involved in the manufacture of non-stick materials and received an EPA health advisory in February 2019.
The cost of replacing a set of filters is approximately US$60, or the six-month replacement period recommended by Aquasana is US$120 per year. Moreover, the system is only larger than a few cans of soda and does not take up a lot of valuable space under the sink. This widely used system uses high-quality metal hardware, and its taps come in a variety of finishes.
The AO Smith AO-US-200 is the same as the Aquasana AQ-5200 in terms of certification, specifications and dimensions. It is unique to Lowe’s and therefore is not so widely available.
AO Smith AO-US-200 is identical to Aquasana AQ-5200 in every important aspect. (This is because AO Smith acquired Aquasana in 2016.) It has the same excellent certification, all-metal hardware, and compact form factor, but because it is only sold at Lowe’s, its sales range is not wide, and its faucet There is only one finish: brushed nickel. If this suits your style, we recommend shopping between the two models at a price: one or the other is often discounted. Filter replacement costs are similar: about $60 for a set, or $120 per year for the six-month cycle recommended by AO Smith.
AQ-5300+ has the same excellent certification, but with higher flow rate and filtration capacity, it is suitable for households with large water consumption, but the cost is higher and it takes up more space under the sink.
Aquasana AQ-5300+ maximum flow has the same 77 ANSI/NSF certifications as our other preferred products, but offers higher flow (0.72 and 0.5 gallons per minute) and filter capacity (800 and 500 gallons). This makes it the first choice for families who need a lot of filtered water and want to use it as soon as possible. It also adds a sediment pre-filter, which is not available in the AQ-5200; this may extend the higher flow rate of the pollutant filter in households rich in sediment water. In other words, the AQ-5300+ model (equipped with a three-liter bottle filter) is much larger than the AQ-5200 and AO Smith AO-US-200, but the recommended filter life is the same, six months. And its upfront cost and the cost of replacing the filter are higher (about 80 US dollars for a set or 160 US dollars a year). Therefore, weigh its benefits and higher costs.
Claryum Direct Connect can be installed without drilling 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 a particularly attractive option for renters (they may be prohibited from changing their location) and those who cannot install a separate filter faucet. It doesn’t even have to be installed on the wall of the sink cabinet-it can simply be placed on its side. It offers the same 77 ANSI/NSF certifications as our other Aquasana and AO Smith options, and can provide up to 1.5 gallons of filtered water per minute, more than other products. The rated capacity of the filter is 784 gallons, or approximately six months of use. But it does not have a sediment pre-filter, so if you have sediment problems, it is not a good choice because it will clog. And it’s very large—20½ x 4½ inches—so if your sink cabinet is small or crowded, it may not be suitable.
Aquasana AQ-5200 has obtained the most pollutant certification, is widely available, is reasonably priced, and has a compact structure. It is the first under-tank water filtration system we are looking for.
The AO Smith AO-US-200 is the same as the Aquasana AQ-5200 in terms of certification, specifications and dimensions. It is unique to Lowe’s and therefore is not so widely available.
AQ-5300+ has the same excellent certification, but with higher flow rate and filtration capacity, it is suitable for households with large water consumption, but the cost is higher and it takes up more space under the sink.
Claryum Direct Connect can be installed without drilling 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 a detailed conversation with the filter certification organization to understand how their testing was conducted, and delved into their public database to confirm that the manufacturer’s statement was supported for certification testing. I also talked with representatives of several water filter manufacturers, including Aquasana/AO Smith, Filtrete, Brita, and Pur, to ask them what they said. And I have personally experienced all of our options, because overall livability, durability and user-friendliness are very important for devices that you use multiple times a day. Former NOAA scientist John Holecek researched and wrote an early Wirecutter water filter guide, conducted his own tests, commissioned further independent tests, and taught me a lot of what I know. My work is built on his foundation.
Unfortunately, there is no uniform answer to whether a water filter is needed. In the United States, public water supply is regulated by the EPA in accordance with the Clean Water Act, and water leaving public water treatment plants must meet strict quality standards. But not all potential pollutants are regulated. Similarly, pollutants can enter the water after leaving the treatment plant by infiltrating into or leaching from leaking pipelines (PDF). Water treatment done (or neglected) at the factory can exacerbate leaching in downstream pipelines—as happened in Flint, Michigan.
To accurately understand the ingredients in the water when the supplier leaves the factory, you can usually find the consumer confidence report of the local supplier’s EPA on the Internet; if not, all public water suppliers must provide you with their CCR according to your requirements . However, due to potential downstream pollution, the only way to determine the composition of your water is to ask a local water quality laboratory for testing.
Based on experience: the older your house or community, the greater the risk of downstream pollution. The U.S. Environmental Protection Agency stated that “houses built before 1986 are more likely to use lead pipes, fixtures, and solder”-once common old materials that did not meet current specifications. Age also increases the likelihood of groundwater contamination left by the former regulatory industry, which can be a risk, especially when combined with degradation associated with aging underground pipelines.
If your family drinks more than two to three gallons of drinking water a day, then an under-sink filter may be better than a tank filter. The system under the sink provides filtered drinking water on demand, without waiting for the completion of the filtration process, just like a water tank. “On-demand” filtration 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 will never refill the pot repeatedly for this.
Compared with sink filters, under sink filters tend to have a larger capacity and longer service life-usually hundreds of gallons and six months or more, while most sink filters are 40 gallons And two months. Because under-sink filters use water pressure instead of gravity to push water through the filter, their filters can be denser, so they can remove a wider range of potential contaminants.
The downside is that they are more expensive than pitcher filters, and the absolute value and average time to replace the filters are also more expensive. The system also takes up space in the sink cabinet that could otherwise be used for storage.
Installing the filter under the sink requires basic plumbing and hardware installation, but this job is simple only if your sink already has a separate tap hole. If not, you need to knock out the location of a built-in faucet (you can see the raised disc on the steel sink, or the mark on the synthetic stone sink). If the percussion hole is missing, you need to drill a hole in the sink. If your sink is installed at the bottom, you also need to drill a hole on the countertop. If you currently have a soap dispenser, an air gap in a dishwasher, or a hand-held sprayer on the sink, you can remove it and install it there.
After testing, we have replaced the discontinued Pur Pitcher filter with a Faster Pour Pitcher filter.
This guide is about a specific type of under-sink filter: those that use a cartridge filter and send the filtered water to a separate tap. These are the most popular under-sink filters. They take up very little space and are usually easy to install and maintain. They use adsorbent materials—usually activated carbon and ion exchange resins, like water tank filters—to bind and neutralize contaminants. We are not talking about filters, reverse osmosis systems, or other pitchers or dispensers installed on taps.
To ensure that we only recommend trustworthy filters, we have always insisted that our selection has passed industry standard certification: ANSI/NSF. The American National Standards Institute and NSF International are private non-profit organizations that work with the EPA, industry representatives, and other experts to establish strict quality standards and testing protocols for thousands of products, including water filters. The two main certification laboratories for water purifiers are NSF International itself and the Water Quality Association (WQA). Both are fully accredited by ANSI and the Canadian Standards Council in North America, can be tested for ANSI/NSF certification, and both must comply with exactly the same test standards and protocols. The filter can only meet the certification standards after it has far exceeded its expected life. Use prepared “challenging” samples, which are much more contaminated than most tap water.
In this guide, we focus on filters that have chlorine, lead, and VOC (a.k.a. volatile organic compound) certifications.
Chlorine certification (under ANSI/Standard 42) is important because chlorine is usually the main culprit for “bad taste” tap water. But this is almost a gimmick: almost all types of water filters have passed its certification.
Lead certification is difficult to achieve because it means reducing lead-rich solutions by more than 99%.
VOC certification is also challenging because it means that the filter can actually remove more than 50 organic compounds, including many common biocides and industrial precursors. Not all under-sink filters have these two certifications, so by focusing on filters with two certifications, we have identified those with significantly superior performance.
We narrowed our search further and chose filters that were additionally certified under the relatively new ANSI/NSF Standard 401, which covers emerging contaminants, such as drugs, that are increasingly found in American waters. Similarly, not all filters have 401 certification, so the filters that have it (and lead and VOC certification) are a very selective group.
In this strict subset, we then look for those with a minimum capacity of 500 gallons. This is equivalent to a filter life of approximately 6 months under heavy use (2¾ gallons per day). For most families, this is enough to meet daily drinking and cooking needs. (The manufacturer provides a recommended filter replacement schedule, usually in months rather than gallons; we follow these recommendations in our evaluations and cost calculations. We recommend always using the original manufacturer’s replacement instead of a third-party filter. )
Finally, we weighed the upfront cost of the entire system and the ongoing cost of replacing the filter. We have not set a lower or upper price limit, but our research shows that although the upfront cost ranges from US$100 to US$1,250, and the filter cost ranges from US$60 to nearly US$300, these differences are not significantly superior. The more expensive model in the specifications. We found several types of under-sink filters that cost well under US$200, while providing excellent certification and longevity. These became our finalists. In addition, we are also looking for:
During the research, we occasionally encountered catastrophic leak reports from the owner of the water filter under the sink. Since the filter is connected to the cold water inlet pipe through a pipe, if the connector or hose is broken, the water will escape until the shut-off valve is closed-which means that it may take hours or even days for you to discover the problem, which will give you Bring serious consequences. Water damage. This is not common, but you need to weigh the risks when considering buying a filter under the sink. If you buy it, please follow the installation instructions carefully, taking care not to cross the connector threads, and then slowly turn on the water to check for leaks.
The reverse osmosis or R/O filter originally used the same type of cartridge filter as we selected here, but added a secondary reverse osmosis filtration mechanism: a fine-pored membrane that allows water to pass through but filters out dissolved minerals. Substances and other substances.
We may discuss R/O filters in depth in future guides. Here, we flatly rejected them. Compared with adsorption filters, they provide limited functional advantages; they generate a lot of waste water (usually 4 gallons of wasted “flush” water per gallon of filtration), while adsorption filters do not; they take up space It is much larger because, unlike adsorption filters, they use 1 gallon or 2 gallon tanks to store filtered water; they are much slower than adsorption filters under the sink.
In the past few years, we have conducted laboratory tests on water filters. The main conclusion we have drawn from the tests is that ANSI/NSF certification is a reliable measure of filter performance. Given the extreme rigor of certification testing, this is not surprising. Since then, we have relied on ANSI/NSF certification instead of our own limited testing to select our competitors.
In 2018, we tested the popular Big Berkey water filtration system, which was not certified by ANSI/NSF, but claimed to have been extensively tested in accordance with ANSI/NSF standards. That experience further consolidated our insistence on true ANSI/NSF certification and our distrust of the “ANSI/NSF tested” statement.
Since then, including 2019, our tests have focused on real-world usability and various practical features and shortcomings that will become apparent when you use these products.
Aquasana AQ-5200 has obtained the most pollutant certification, is widely available, is reasonably priced, and has a compact structure. It is the first under-tank water filtration system we are looking for.
We chose Aquasana AQ-5200, also known as Aquasana Claryum Dual-Stage. So far, its most important feature is that its filter has obtained the best ANSI/NSF certification among our competitors, including chlorine, chloramine, lead, mercury, VOC, a variety of “emerging pollutants”, and perfluorooctanoic acid and Perfluorooctane sulfonic acid. In addition, its faucet and plumbing hardware are made of solid metal, which is better than the plastics used by some other manufacturers. And this system is also very compact. Finally, the Aquasana AQ-5200 is one of the most valuable products we found in the filter under the sink. The prepaid cost of the entire system (filter, housing, faucet and hardware) is usually US$140, and two are US$60. Replace the filter. This is less than many competitors with weaker certifications.
Aquasana AQ-5200 has passed ANSI/NSF certification (PDF) and can handle 77 pollutants. Together with the same certified Aquasana AQ-5300+ and AO Smith AO-US-200, this makes AQ-5200 the most powerful certification 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 series.) In contrast, the excellent Pur Pitcher Filter with Lead Reduction is certified at 23.
These certifications include chlorine, which is used to kill pathogens in municipal water supplies and is the main cause of “smelling” tap water; lead, which can be leached from old pipes and pipe solder; mercury; live Cryptosporidium and Giardia , Two potential pathogens; chloramine is a persistent chloramine disinfectant, which is increasingly used in filtration plants in the southern United States, where pure chlorine will rapidly degrade in warm water. Aquasana AQ-5200 has also passed the certification of 15 “emerging pollutants”, which are increasing in public water supply systems, including bisphenol A, ibuprofen, and estrone (an estrogen used for contraception) ; For PFOA and PFOS-fluorine-based compounds used to make non-stick substances, and received an EPA health advisory in February 2019. (At the time of consultation, only three manufacturers of this type of filter have obtained PFOA/S certification, which makes this particularly noteworthy.) It has also passed VOC certification. This means that it can effectively remove more than 50 different organic compounds, including many pesticides and industrial precursors.
In addition to activated carbon and ion exchange resins (most, if not all, under-tank filters are common), Aquasana also uses two additional filtration technologies to obtain certification. For chloramines, it adds catalytic carbon, which is a more porous form of activated carbon produced by treating carbon with high-temperature gas. For Cryptosporidium and Giardia, Aquasana makes filters by reducing the pore size to 0.5 microns, which is enough to physically capture them.
The excellent certification of the Aquasana AQ-5200 filter is the main reason we chose it. But its design and materials also make it unique. The faucet is made of solid metal, as is the T-shaped fixture that connects the filter to the pipe. Some competitors use plastic for one or two of them, reducing costs, but increasing the risk of thread cross-threading and installation errors. AQ-5200 uses compression fittings to ensure a tight and safe seal between your pipe and the plastic pipe that carries water to the filter and faucet; some competitors use simple push-in fittings, which are not very safe. The AQ-5200 faucet is available in three finishes (brushed nickel, polished chrome and oiled bronze), and some competitors have no choice.
We also like the compact form factor of the AQ-5200 system. It uses a pair of filters, each of which is a little larger than a soda can; some other filters, including the Aquasana AQ-5300+ below, are the size of a liter bottle. After installing the filter on the mounting bracket, the dimensions of AQ-5200 are 9 inches high, 8 inches wide, and 4 inches deep; Aquasana AQ-5300+ is 13 x 12 x 4 inches. This means that the AQ-5200 occupies much less space in the sink cabinet, can be installed in a narrow space that cannot be accommodated by larger systems, and leaves more space for storage under the sink. You need approximately 11 inches of vertical space (measured down from the top of the enclosure) to allow the filter to be replaced, and approximately 9 inches of unobstructed horizontal space along the cabinet wall to install the enclosure.
The AQ-5200 is well-reviewed for water filters, with 4.5 stars out of more than 800 reviews on the Aquasana website (out of five stars), and 4.5 stars out of nearly 500 reviews on Home Depot.
Finally, Aquasana AQ-5200 currently costs about US$140 for the entire system (usually close to US$100), and a set of replacement filters costs US$60 (every six-month replacement period is US$120 per year). Aquasana AQ- The 5200 is one of our competitors’ most valuable products, hundreds of dollars cheaper than some less widely certified models. The device includes a timer that will start beeping when you need to change the filter, but we recommend that you also set a repeat calendar reminder on your phone. (You are unlikely to miss it.)
Compared to some competitors, the Aquasana AQ-5200 has a lower maximum flow rate (0.5 gpm vs. 0.72 or higher) and lower capacity (500 gallons vs. 750 or higher). This is a direct result of its physically small filter. In general, we believe that these small shortcomings are offset by its compactness. If you know that you want higher flow and capacity, Aquasana AQ-5300+ has a rated flow of 0.72 gpm and 800 gallons, but with the same six-month filter replacement schedule, Aquasana Claryum Direct Connect has a flow rate of up to 1.5 gpm and Rated to 784 gallons and six months.