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        Big Berkey water filters have a cult following. We’ve been researching the best water filter pitchers and the best under sink water filters for years, and we’ve been asked about the Big Berkey many times. The manufacturer claims that this filter can remove more contaminants than other filters. However, unlike our other filter options, Big Berkey is not independently certified to NSF/ANSI standards.
        After 50 hours of research and independent lab testing of manufacturer Big Berkey’s claims, our test results, as well as the results of another lab we spoke with and a third lab whose results are publicly available, are not entirely consistent. We believe this further illustrates the importance of NSF/ANSI certification: it allows people to make purchasing decisions based on a reliable apples-to-apples performance comparison. Additionally, since the Big Berkey system is larger, more expensive, and more difficult to maintain than under-sink pitchers and filters, we wouldn’t recommend it even if it were certified.
        Berkey countertop systems and filters are much more expensive than other water filtration options and less convenient to use. Manufacturers’ performance claims are not independently certified to national standards.
        New Millennium Concepts, the manufacturer of the Big Berkey, claims that the filter can remove over a hundred contaminants, which is much more than other gravity-fed filters we’ve reviewed. We tested these claims on a limited scale, and our results were not always consistent with laboratory results commissioned by New Millennium. Specifically, results from the laboratory we commissioned and from the laboratory New Millennium had recently contracted showed that chloroform filtration was not as effective as a third earlier test (which was also reported in New Millennium’s product literature).
        None of the testing we cite here (neither our testing nor Envirotek testing or Los Angeles County Laboratory’s New Millennium contract testing) meets the rigor of NSF/ANSI testing. Specifically, NSF/ANSI required that the type of filter used by Berkey must pass twice the rated capacity of the filter through which the wastewater is being measured before taking measurements. While all of the tests we contract with New Millennium are, to the best of our knowledge, thorough and professional, each uses its own, less labor-intensive protocol. Since none of the testing was conducted to the full NSF/ANSI standards, we have no clear way to accurately compare the results or compare the overall performance of the Burkey filter to what we have tested in the past.
        One area where everyone agreed was in removing lead from drinking water, which showed that Big Berkey did a good job of removing heavy metals. So if you have a known problem with lead or other metals in your water, it may be worth looking into Big Berks as a temporary measure.
        In addition to the difficulty of comparing conflicting laboratory results, New Millennium Concepts did not respond to multiple interview requests to discuss our findings. Overall, our reports give us a vague understanding of Berkey’s systems, which is not the case with many other filter manufacturers.
        For everyday water filtration, most NSF/ANSI certified pitcher and under-sink filters are smaller, more convenient, cheaper to purchase and maintain, and easier to use. They also provide the accountability associated with independent and transparent testing.
        Keep in mind that most municipal water systems are inherently safe, so unless you know there is a problem locally, you probably won’t need filtration for health reasons. If emergency preparedness is a major concern for you, consider tips from our emergency preparedness guide, which includes products and tips for keeping clean water accessible.
        Since 2016, I have overseen our guide to water filters, including pitchers and under-sink systems. John Holecek is a former NOAA researcher who has been conducting air and water quality testing for us since 2014. He produced test solutions and worked with independent labs on behalf of Wirecutter to write this guide and the pitcher filter guide. EnviroMatrix Analytical is accredited by the California Department of Public Health to routinely test drinking water.
        Big Berkey filtration systems and similar systems from Alexapure and ProOne (formerly Propur) are popular among people who rely on well water, which may contain contaminants that would otherwise be removed by municipal water treatment plants. Burkey also has a large following among disaster preparedness experts and government skeptics. 1 Berkey retailers advertise these systems as emergency safety devices, and by some estimates they can provide filtered drinking water to up to 170 people per day.
        Whatever the reason for your interest in Berkey or any other water filtration system, we must emphasize that most municipal water in the United States is very clean to begin with. No filter can remove contaminants that aren’t already there, so unless you have a known problem, you probably won’t need a filter at all.
        The makers of the Big Berkey claim that the device can remove over a hundred contaminants (many more than any other gravity-fed filter we’ve reviewed). Since this filter is not NSF/ANSI certified (unlike all the other filters we recommend in other guides), we don’t have a solid basis to compare it to other filters we’ve tested in the past. So we decided to conduct independent testing to try to replicate some of these results.
        To test these claims, as with the canister test, John Holecek prepared what he called “problem solutions” and ran them through a Big Berkey system (equipped with a Black Berkey filter). He then sent samples of the solution and filtered water to EnviroMatrix Analytical, an independent laboratory accredited by the State of California, for analysis. To perform the Big Burkey test, he prepared two solutions: one containing a large amount of dissolved lead, and the other containing chloroform. They will give an idea of ​​the overall efficiency of the filter in relation to heavy metals and organic compounds.
        John prepared control samples to meet or exceed the contaminant concentrations specified in the NSF/ANSI certification (150 µg/L for lead and 300 µg/L for chloroform). According to the Berkey dye test (video), after confirming that the filter was installed and functioning correctly, he ran a gallon of the contaminated solution through the Berkey and discarded the filtrate (water and anything else that passed through the filter). To measure the contaminated solution, he filtered a total of two gallons of liquid through Burkey, removed a control sample from the second gallon, and collected two test samples of the filtrate from it. Control and leachate samples were then sent to EnviroMatrix Analytical for testing. Because chloroform is very volatile and “wants” to evaporate and combine with other compounds present, John mixes chloroform into the contaminant solution just before filtration.
        EnviroMatrix Analytical uses gas chromatography-mass spectrometry (GC-MS) to measure chloroform and any other volatile organic compounds (or VOCs). Lead content was measured using inductively coupled plasma mass spectrometry (ICP-MS) according to EPA Method 200.8.
        EnviroMatrix Analytical’s results partially contradict and partially support New Millennium’s claims. Berkey black filters are less effective at removing chloroform. On the other hand, they do a very good job of reducing lead. (See next section for full results.)
        We shared our lab results with Jamie Young, a chemist and owner/operator of a New Jersey licensed water testing laboratory (then known as Envirotek) regulated by New Millennium Concepts (creator of the Big Berkey system) commissioned in 2014. your own testing. This is a Black Berkey filter. 2 Young confirmed our findings with chloroform and lead.
        New Millennium has commissioned other tests in the past, including one in 2012 conducted by the Los Angeles County Agricultural Commissioner/Department of Weights and Measures Environmental Toxicology Laboratory; in this report, chloroform (PDF) is indeed listed as Black Berkey according to department standards (EPA, not one of the contaminants removed by NSF/ANSI). After testing in 2012, toxicology work was transferred to the Los Angeles Department of Public Health. We contacted DPH and they confirmed that the original report was accurate. But New Millennium described Young’s testing as the “latest round” and his results are the latest listed in the Birkey Water Knowledge Base, which New Millennium maintains to list test results and answer frequently asked questions on an independent website.
        Wirecutter, Young and Los Angeles County’s testing protocols are inconsistent. And since none of them meet NSF/ANSI standards, we have no standard basis for comparing results.
        Thus, our overall opinion of the Big Berkey system does not depend greatly on the results of our tests. The Big Berkey is easy enough to use and cost-effective that we recommend a regular gravity-fed canister filter for most readers, even though the Berkey does everything New Millennium claims it can do as a filter.
        We also cut open a couple of Black Berkey filters to see how they’re constructed and to find evidence that they contain “at least” six different filter elements, as Berkey’s marketing department claims. We found that while the Berkey filter is larger and denser than the Brita and 3M Filtrete filters, they appear to have the same filtration mechanism: activated carbon impregnated with an ion exchange resin.
        Berkey filtration systems fall into the large category of gravity-fed filters. These simple devices use gravity to draw source water from an upper chamber through a fine mesh filter; the filtered water is collected in the lower chamber and can be distributed from there. This is an effective and widely used method, of which canister filters are a common example.
        Berkey filters are highly effective in treating drinking water contaminated with lead. In our testing, they reduced lead levels from 170 µg/L to just 0.12 µg/L, which far exceeds the NSF/ANSI certification requirement of reducing lead levels from 150 µg/L to 10 µg/L or lower.
        But in our tests with chloroform, the Black Berkey filter performed poorly, reducing the chloroform content of the test sample by just 13%, from 150 µg/L to 130 µg/L. NSF/ANSI requires a 95% reduction from 300 µg/L to 15 µg/L or less. (Our test solution was prepared to the NSF/ANSI standard of 300 µg/L, but the volatility of chloroform means it quickly forms new compounds or evaporates, so its concentration drops to 150 µg/L when tested. But the EnviroMatrix Analytical test also captures (other volatile organic compounds that chloroform can produce, so we believe the results are accurate.) Jamie Young, a licensed water testing engineer from New Jersey who conducted the latest round of testing for New Millennium Concepts, also performed poorly with chloroform from Black Berkey filter
        However, New Millennium Concepts claims on the filter box that the Black Berkey filter reduces chloroform by 99.8% to “below laboratory detectable limits.” (This number appears to be based on test results conducted by the Los Angeles County Laboratory in 2012. Test results [PDF] are available in the Berkey Water knowledge base, linked to (but not part of) the main Berkey site.)
       To be clear, neither we, Envirotek, nor Los Angeles County have replicated the entire NSF/ANSI Standard 53 protocol used for gravity filters such as the Black Berkey.
        In our case, we performed a laboratory test after the Black Berkeys filtered several gallons of the prepared solution to the NSF/ANSI reference concentration. But NSF/ANSI certification requires gravity-fed filters to withstand twice their rated flow capacity before testing. For the Black Berkey filter, that means 6,000 gallons.
        Like us, Jamie Young prepared the test solution to NSF/ANSI Standard 53, but it did not go through the full Standard 53 protocol, which required 6,000 gallons of the contaminant solution used by Black Berries to pass through the filter. He reported that in his tests the filter also performed well with lead, which confirmed our own findings. However, he said they no longer meet NSF removal standards after filtering about 1,100 gallons—just over one-third of New Millennium’s claimed 3,000-gallon lifespan for Black Berkey filters.
        Los Angeles County follows a separate EPA protocol in which only one 2-liter sample of the sample solution passes through the filter. Unlike us and Young, the district found that the Black Berkey filter removed chloroform to test standards, in this case greater than 99.8%, from 250 µg/L to less than 0.5 µg/L.
       The inconsistent results from our testing compared to those from the two labs commissioned by Burkey make us hesitant to recommend this filter, especially when you can find other independently certified options that address all of these open questions.
        Overall, our testing experience supports our position: we recommend water filters with NSF/ANSI certification, while Berkey does not have such certification. This is because the NSF/ANSI certification standards are extremely strict and transparent: anyone can read them on the NSF website. Independent laboratories approved for NSF/ANSI certification testing are themselves strictly accredited. When we wrote about this guide, we spoke with NSF and learned that it would cost more than $1 million to conduct certification testing of all the substances that New Millennium Concepts claims the Black Berkey filter removes. New Millennium said it believes NSF certification is unnecessary, citing cost as another reason it has not yet conducted testing.
        But even regardless of actual filtration performance, there are enough real problems with this filter that it’s easy for us to recommend one of our other water filter options before recommending the Big Berkey. First, the Berkey system is significantly more expensive to purchase and maintain than any filter we recommend. Unlike the filters we recommend, the Berkey is large and attractive. It is designed to be placed on a tabletop. But since it’s 19 inches tall, it won’t fit under many wall cabinets, which are typically installed 18 inches above the countertop. The Berkey is also too tall to fit most refrigerator configurations. This way, you’re less likely to keep the water in Berkey cold (which is easy to do with our sailor’s pick with filter). New Millennium Concepts offers a 5-inch bracket to make it easier to mount goggles under the Big Berkey pipe, but these brackets cost more and add height to an already tall unit.
        A Wirecutter writer who once owned a Big Berkey wrote about his experience: “Aside from the fact that the device is ridiculously large, the top tank can easily overfill if you forget to empty the bottom tank. a little heavy and bulky and it starts filtering right away. So you’ll have to lift it up to make room for the carbon filter (which is long and flimsy) and then put it in the bottom sink before it starts leaking onto the floor or counter. “
        Another Wirecutter editor had a Big Berkey (with the company’s replaceable ceramic filter) but quickly stopped using it. “It was a gift from my spouse because I saw one at a friend’s house and thought the water that came out tasted really good,” he said. “Living with one was a completely different matter. The countertop area, both horizontally and vertically, was huge and inconvenient. And the kitchen sink we lived in was so small that it was a chore to clean.”
        We also see many owners complaining about algae and bacteria growth and, most often, mucus in their Great Berkies. New Millenium Concepts recognizes this problem and recommends adding Berkey Biofilm Drops to filtered water. This is a serious enough issue that many Berkey dealers have dedicated an entire page to it.
        Many dealers acknowledge that bacterial growth can be a problem, but often claim that it will show up after a few years of use, but this is not the case with our editors. “It started in less than a year,” he said. “The water tastes musty, and both the upper and lower chambers begin to smell musty. I clean it thoroughly, rinse the filters and remove them to get to all the tiny connections, and make sure to wash the inside of the faucet. In about two or three days. After a few days the smell of the water became normal and then became moldy again. I ended up stopping Birki and I felt bad.”
        To completely remove algae and bacterial slime from a Black Berkey filter, clean the surface with Scotch-Brite, do the same for the top and bottom reservoirs, and finally run a bleach solution through the filter. It requires a lot of maintenance for something designed to make people feel secure about their water.
        If you care about disaster preparedness and want to ensure you have clean water available during emergencies, we recommend using the water storage products in our Emergency Preparedness Guide. If you just want a good tap water filter, we recommend looking for an NSF/ANSI certified filter, such as our guides to the Best Water Filter Pitchers and the Best Under Sink Water Filters.
        Most gravity filters use two different materials to remove contaminants from water. Activated carbon adsorbs or chemically binds organic compounds, including fuels and petroleum-based solvents, many pesticides and many pharmaceuticals. Ion exchange resins remove many dissolved metals from water, replacing toxic heavy metals (such as lead, mercury and cadmium) with lighter, mostly harmless heavy metals (such as sodium, the main component of table salt).
        Our selection of pitcher filters (from Brita) and under-sink filters (from 3M Filtrete) are designed this way. New Millennium Concepts does not disclose what the Black Berkey filter is made of, but several retailers tout its design, including TheBerkey.com: “Our Black Berkey filter element is made from a proprietary blend of over six different media. The formula consists of various types, including high-quality coconut shell carbon, all embedded in a very compact matrix containing millions of microscopic pores.” When we cut into a pair of Black Berkey filters, they were made up of impregnated ions containing activated carbon blocks exchanging resin. Jamie Young confirms this observation.
        Tim Heffernan is a senior writer specializing in air and water quality and home energy efficiency. A former contributor to The Atlantic, Popular Mechanics and other national magazines, he joined Wirecutter in 2015. He has three bikes and zero gears.
       These water filters, pitchers and dispensers are certified to remove contaminants and improve the quality of drinking water in your home.
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        Wirecutter is The New York Times’ product recommendation service. Our reporters combine independent research with (sometimes) rigorous testing to help you make a buying decision quickly and confidently. Whether you’re looking for quality products or looking for helpful advice, we’ll help you find the right answers (the first time).