Berkey vs Propur (ProOne): 2026 Comparison After the Culligan Change

Last updated: August 23, 2026 | By Dan DeBaun

Berkey vs Propur is no longer a comparison between two competing brands, because the Propur brand is being retired. Propur was renamed ProOne around 2020, Culligan later acquired ProOne, and Culligan states that ProOne products are now available only while remaining inventory lasts before being replaced by the Culligan MaxClear line. Berkey systems remain in full production, with Black Berkey filter elements rated for 6,000 gallons per pair and replacement costs of roughly 2 to 3 cents per gallon. This article explains what happened to Propur, compares the Big Berkey against the ProOne Big+ as both stand in 2026, and covers what the change means whether you are buying new or already own a Propur or ProOne system.

What happened to Propur?

Propur no longer exists as an active brand, and ProOne, its successor, is being phased out by Culligan. The timeline runs in three stages. Propur launched in Michigan as a gravity filter company founded by a former Berkey dealer, which is why its stainless steel systems look and work so much like a Berkey. Around 2020 the company rebranded as ProOne, keeping the same product line: the Big+, Traveler+, Big II, and the ProOne G series filter elements. Culligan then acquired ProOne, and Culligan's own transition page states that ProOne products will be sold only while current inventory lasts, after which the line continues as Culligan with MaxClear Technology, offered in a single 7 inch filter size.

As of August 2026, ProOne's website lists the Big+ system at $183.96, marked down from $229.95, with a note that it is discontinued and available while supplies last. For a full comparison against the successor product, see our Berkey vs Culligan MaxClear comparison, which covers the new platform in detail.

If you already own a Propur or ProOne system, you are not stranded. Culligan states that MaxClear replacement filters fit existing ProOne and Propur systems, including the Big+, Traveler+, Big II, King, and Nomad, so consumables remain available under the new name.

Big Berkey vs ProOne Big+ at a glance

The Big Berkey holds less water than the Big+ but filters roughly three times faster, and its filter elements are rated for years of use rather than months. Here is the side by side as of August 2026.

Swipe left to see the full table

Independent testing and certifications

ProOne holds the stronger formal certification badges, and Berkey publishes the deeper body of test data. Both facts matter, and which one matters more depends on how you evaluate a filter.

ProOne's G3.0 elements are IAPMO R&T certified against NSF/ANSI 372 for lead-free materials, NSF/ANSI 42 for chlorine and particulates, NSF/ANSI 53 for lead and total PFAS, and NSF/ANSI 401 for microplastics. That is a legitimate, verifiable credential, and ProOne publishes its lab report page for anyone who wants to check the underlying numbers.

Berkey's approach centers on breadth of published data. Black Berkey elements have been tested by independent, accredited labs against more than 200 drinking water contaminants, including heavy metals, VOCs, pharmaceuticals, herbicides, and 25 PFAS compounds reduced to non-detectable levels, with the full downloadable reports on our test results page. The current Berkey Phoenix elements are certified to NSF/ANSI 42 and 372, follow NSF/ANSI 53 test protocols, and publish their complete lab data on the Phoenix lab results page. To be precise about the distinction: Phoenix is not certified to Standard 53, while ProOne's element is, and ProOne's certification covers 13 contaminants while Berkey's published testing covers more than 200. Berkey's testing record has also been covered by outlets including EWG, Food Network, CBS, and the LA Times, collected on our media coverage page.

One honest note: if a formal NSF/ANSI 53 certification badge is the single factor that decides your purchase, the ProOne G3.0 and its Culligan MaxClear successor carry it and current Berkey elements do not. If you want the widest tested contaminant range with the numbers published for you to read, that is where Berkey is strongest.

Flow rate, capacity, and daily use

The Big Berkey filters about 3.5 gallons per hour with its standard two Black Berkey elements, and about 7 gallons per hour with four fitted. The ProOne Big+ moves roughly 1 gallon per hour with two filters fitted, so refilling in the morning and waiting is a bigger part of ProOne ownership. The Big+ counters with a slightly larger 3 gallon holding capacity against the Big Berkey's 2.25 gallons.

ProOne wins on out-of-box convenience. Its filters need no priming, just a rinse, and a stainless steel spigot and stand come standard. Black Berkey elements need to be primed before first use, which takes a few minutes per element, and the standard Berkey spigot is plastic with stainless available as an upgrade. ProOne also builds fluoride reduction into its main element, while Berkey handles fluoride and arsenic with optional PF-2 filters at $103 per set of two, which fit in the lower chamber.

Berkey wins on range of models. The line runs from the 1.5 gallon Travel Berkey at $327 through the Big Berkey at $367, the 3.25 gallon Royal at $408, the 4.5 gallon Imperial at $451, and the 6 gallon Crown at $478, so households from one person to twelve can size the system to match. ProOne offered three sizes, all now on closeout.

Long-term cost: where the two systems separate

Filter replacement economics are the largest real difference between these systems, larger than any spec on the comparison table. Berkey rates its elements by volume, ProOne rates its elements by time, and that changes what you spend over five years.

A pair of Black Berkey elements is rated for 6,000 gallons. A household filtering 2 gallons a day uses about 3,650 gallons in five years, which means the pair that came with the system is typically still working at the five year mark. ProOne's guidance for the G3.0 7 inch element is replacement every 6 months or about 1,000 gallons, whichever comes first. At 2 gallons a day you reach the 6 month clock long before the gallon limit, so following the manufacturer's schedule with two filters fitted means buying about four replacement elements per year.

To be fair to ProOne, some owners stretch filters to the gallon rating rather than the calendar. Even on that most generous reading, a $158 pair of G3.0 elements rated at 2,000 combined gallons works out to about 8 cents per gallon, which is still three to four times the cost of Black Berkey elements at $166 per 6,000 gallon pair or Phoenix elements at $120 per 5,500 gallon pair. There is no usage pattern where ProOne's consumables come out cheaper.

Frequently asked questions

Is Propur the same as ProOne?

Yes. Propur rebranded as ProOne around 2020, and the products stayed the same line under the new name. Culligan later acquired ProOne and is now transitioning the products to the Culligan MaxClear name.

Is ProOne being discontinued?

Yes. Culligan states that ProOne products are available only while current inventory lasts, and ProOne's own site lists systems like the Big+ as discontinued closeout items. The line continues under the Culligan MaxClear name with a single 7 inch filter size.

Can I still get replacement filters for a Propur or ProOne system?

Yes. Culligan MaxClear replacement filters are designed to fit existing ProOne and Propur systems, including the Big+, Traveler+, Big II, King, and Nomad. Remaining ProOne G3.0 inventory is also still being sold while it lasts.

How long do Berkey filters last compared to ProOne filters?

Black Berkey elements are rated for 6,000 gallons per pair, which is typically years of household use. ProOne G3.0 elements are rated for 6 months or about 1,000 gallons per 7 inch element, whichever comes first, so they are replaced on a schedule rather than by volume for most households.

Is ProOne NSF certified?

ProOne G3.0 elements are IAPMO certified against NSF/ANSI standards 42, 53 for lead and total PFAS, 401 for microplastics, and 372 for lead-free materials. Berkey Phoenix elements are certified to NSF/ANSI 42 and 372, and Black Berkey elements have published independent lab testing against more than 200 contaminants.

Which is cheaper long term, Berkey or ProOne?

Berkey, by a wide margin. Over five years at 2 gallons per day, a Big Berkey runs about $367 all-in because the included filter pair is rated for 6,000 gallons, while a ProOne Big+ following its 6 month replacement schedule runs about $1,650. Even stretching ProOne filters to their full gallon rating leaves them three to four times more expensive per gallon.

Do Berkey filters remove fluoride?

Fluoride reduction requires the optional PF-2 filters, which cost $103 per set of two and attach to the filter elements in the lower chamber. ProOne builds fluoride reduction into its main G3.0 element, which is a genuine convenience advantage for ProOne.

Verdict: which should you buy in 2026?

For a new purchase, the Big Berkey is the stronger buy, and the brand situation makes this the clearest this comparison has ever been. Berkey systems are in full production with filter elements rated in thousands of gallons, replacement costs of 2 to 3 cents per gallon, and the most extensive published test data in gravity filtration. ProOne hardware is solid and its certifications are real, but the brand is being retired, its systems are on closeout, and its filter economics run three to four times higher per gallon under any usage pattern.

A discounted ProOne Big+ can still make sense in two cases: you want the NSF/ANSI 53 certification badge above all other factors, or you find remaining inventory priced low enough that you are comfortable owning a system whose brand is mid-transition. Existing Propur and ProOne owners do not need to switch, since Culligan MaxClear filters fit those systems. If you are weighing Berkey against the successor product rather than the closeout, read our Berkey vs Culligan MaxClear comparison, and for another matchup against a Berkey offshoot, see Berkey vs Boroux.