Both products sit on a countertop. Both require zero installation. That’s genuinely where the similarities stop.
Berkey uses gravity filtration through proprietary elements. AquaTru uses a small electric pump to push water through an RO membrane. The technology difference determines everything about performance, use case, and what you can trust about their claims.
How They Work
Berkey: water poured into the upper chamber drips through Black Berkey filter elements via gravity. The elements use a combination of activated carbon and proprietary media. No electricity, no water pressure required. Works completely off-grid. Production rate is roughly 1-7 gallons per hour depending on the chamber size and how full the upper tank is.
AquaTru: a small reservoir holds tap water. An electric pump pressurizes the water through a multi-stage system: sediment pre-filter, activated carbon pre-filter, RO membrane, and carbon post-filter. Produces about 3 cups per 12-15 minute cycle. Requires an outlet.
The Certification Question
This is where the comparison gets meaningful.
AquaTru holds NSF 58 certification (reverse osmosis systems, health-effect contaminant removal) and NSF P473 certification (PFAS removal). These certifications involve independent testing by an accredited third-party organization. The removal percentages are verified by labs that are not paid by the manufacturer to find favorable results.
Berkey does not hold NSF certification. Its contaminant removal claims are supported by lab tests commissioned by Berkey. The company selects and pays for those tests. In 2023, the EPA issued enforcement notices related to Berkey’s marketing claims, specifically regarding its products being marketed as pesticides without EPA registration.
Neither of these facts makes Berkey a bad product. But the documentation standard is different. When Berkey claims PFAS removal, you’re trusting manufacturer-commissioned testing. When AquaTru claims PFAS removal, you’re trusting NSF-verified independent testing.
Contaminant Coverage
AquaTru (NSF-verified): PFAS (>98%), fluoride (93-96%), arsenic, nitrates (83-90%), lead (>96%), chlorine, dissolved minerals. This data comes from NSF-certified testing.
Berkey (manufacturer-commissioned): chlorine, VOCs, pharmaceuticals, heavy metals including lead, fluoride, bacteria, viruses. Independent testing results on PFAS have varied. The wide contaminant list is Berkey’s primary marketing claim. The lack of NSF certification means those claims can’t be verified the same way.
For NSF certification explained, including what each standard number means, see the learn section.
Flow Rate and Daily Capacity
Big Berkey holds 2.25 gallons and produces about 3.5 gallons per hour at full capacity with two Black Berkey elements. For daily drinking needs, it’s functional but requires attention to keeping the upper chamber filled.
AquaTru produces about 3 cups per 12-15 minute cycle. For a household drinking 2 gallons per day, that’s roughly 8-10 cycles. The storage carafe holds a little over half a gallon. It needs to run multiple times to fill for a day’s use.
Neither system is fast. Both require planning ahead. For high-volume households, an under-sink RO with a pressurized storage tank is the more practical daily driver.
Off-Grid and Emergency Use
Berkey is genuinely useful for emergency preparedness. No electricity. No water pressure required. Can filter from sources that aren’t municipal tap water, including well water, stored water, and in emergency situations, surface water (Berkey claims bacterial and protozoa removal). A family with a Big Berkey has a functional drinking water solution during extended power outages.
AquaTru requires power. It requires tap water pressure. It doesn’t function off-grid in any meaningful sense.
If emergency preparedness is part of why you’re buying a countertop filter, Berkey is the only option between these two.
Cost
AquaTru Classic: $130-150 on sale, $170-200 regular price. Filter set replacement (all four stages): approximately $60-70 per year at typical household use.
Big Berkey: $280-350. Black Berkey element pair: $130, rated at 3,000 gallons per pair (6,000 gallons total for two pairs run in parallel). At 2 gallons per day, that’s roughly 8 years of filter life. Annual filter cost works out to $15-20 per year.
Long-term, Berkey has lower filter replacement costs. AquaTru is less expensive to start.
The Recommendation
If certified PFAS removal is your priority, buy AquaTru. NSF P473 certification is the gold standard for PFAS claims, and AquaTru has it. Berkey’s PFAS performance is less reliably documented, and independent testing has shown variable results.
If you want off-grid capability, emergency preparedness as part of the value, or long-term lower filter costs, Berkey has a strong track record despite the certification gap. It solves a different set of problems.
They’re not competing for the same customer. Figure out which problem is actually yours.
See individual reviews at Berkey water filter review and AquaTru countertop review.