
Big Berkey 2.25 Gallon
Score: 78/100
Purewell PW-OB-PH
Score: 72/100Rankings

The Big Berkey is a gravity-fed countertop water filtration system constructed from surgical-grade stainless steel, designed to remove over 200 contaminants without requiring electricity. Its main limitation is the slow filtration speed and lack of official NSF certification for the complete system. It is best suited for small households, off-grid living, and emergency preparedness.

The Purewell 6-Stage system offers high-precision 0.01-micron filtration in a durable stainless steel body, making it excellent for removing microscopic contaminants. However, it lacks TDS reduction capabilities and has a limited water capacity. It is best suited for small households or off-grid use where fine filtration is prioritized over mineral adjustment.
| Attribute | ![]() | ![]() |
|---|---|---|
0.06 GPM | 4 GPMbest | |
60 monthsbest | 6 months | |
2 stages | 6 stagesbest | |
| ↓ lower better | 0 PSIbest | — |
| ↓ lower better | 0.2 microns | 0.01 micronsbest |
| ↓ lower better | 1 ratiobest | — |
0.5 yearsbest | — | |
| ↓ lower better | 21 inches | 20 inchesbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Health & Safety(1) | ||
Remineralization | false | true |
Installation & Compatibility(1) | ||
Installation Type | Countertop | Countertop / Gravity |
Filtration & Performance(4) | ||
Filtration Technology | Gravity | Ultra-Filtration (UF) and Carbon |
Flow Rate (GPM) | 0.06 GPM | 4.0 GPM |
Filtration Stages (stages) | 2 stages | 6 stages |
Micron Rating (microns) | 0.2 microns | 0.01 microns |
Maintenance & Warranty(1) | ||
Filter Lifespan (months) | 60 months | 6 months |
Dimensions & Build(3) | ||
Height (inches) | 21 inches | 20.0 inches |
Width (inches) | 8.5 inches | 8.8 inches |
Depth (inches) | 8.5 inches | 8.8 inches |

Products in the top-left offer the best value (high score, low price).

Professional reviewers and editors praise the Big Berkey for its robust contaminant removal capabilities, noting that it exceeds NSF/ANSI Standard 53 in laboratory settings. Experts highlight its durable stainless steel build and versatility for various water sources. However, they criticize the slow filtration flow rates and the lack of official NSF certification for the complete system.
Everyday users generally praise the Big Berkey for its reliability, long filter life, and ability to purify water without electricity, making it a favorite for families and emergency preparedness. Common recurring complaints include the slow filtration speed, which can take over two hours to fill, and the hassle involved in priming the filters.



Professional reviews highlight the Purewell system as a well-crafted solution for fine filtration needs, praising its 0.01-micron accuracy and durable construction, while noting the inability to reduce TDS.
Users appreciate the ease of use, portability, and effective contaminant removal, though some note the slower flow rate and limited capacity as minor inconveniences.
