Berkey Filters Flow Rate or Filtration Speed
What is a Water Filter Flow Rate?
A water filter flow rate, also known as filtration speed, is the amount of time it takes for the water to go through the filtration process within the system. The rate primarily depends on the size of the water filter system, the type of filter media, the number of water filters within the system, and the quantity of contaminants in the water.
What is the Flow Rate for Berkey Water Filters?
The flow rate for any Berkey water filter system varies. Some may drip, and others create a steady stream of water. Each filter is slightly different and can affect how fast the water flows through the carbon and other interior materials. The average Berkey water filter flow rate is about one gallon per hour with the standard two Black Berkey Filter Elements. For each additional pair of Black Filters expect the time to be cut in half. The more Black Berkey Filters added to a system, the faster the flow rate. The flow rate should be between one gallon per hour with two Black Berkey Filters and four gallons per hour with eight elements.
How Long Should Your Berkey Take to Filter?
Model |
Capacity |
Avg. Filtering Time* |
Flow Rate |
Travel Berkey Water Filter | 1.5 Gallons | 1 hour 30 min (2 Black Berkey filters) | 1 GPH |
Big Berkey Water Filter | 2.25 Gallons |
2 hours 15 min (2 Black Berkey filters) 1 hour 8 min (4 Black Berkey filters) |
1 GPH 2 GPH |
Royal Berkey Water Filter | 3.25 Gallons |
3 hours 15 min (2 Black Berkey filters) 1 hour 38 min (4 Black Berkey filters) |
1 GPH 2 GPH |
Imperial Berkey Water Filter | 4.5 Gallons |
4 hours 30 min (2 Black Berkey filters) 2 hours 15 min (4 Black Berkey filters) 1 hour 8 min (6 Black Berkey filters) |
1 GPH 2 GPH 3 GPH |
Crown Berkey Water Filter | 6 Gallons |
6 hours (2 Black Berkey filters) 3 hours (4 Black Berkey filters) 1 hour 30 min (6 Black Berkey filters) 45 min (8 Black Berkey filters) |
1 GPH 2 GPH 3 GPH 4 GPH |
Berkey Light Water Filter | 2.75 Gallons |
2 hour 45 min (2 Black Berkey filters) 1 hour 23 min (4 Black Berkey filters) |
1 GPH 2 GPH |
*GPH--Gallon Per Hour
*Average filtering time is based off of the rate of one gallon per hour per set of two Black Berkey Filters.
Fixing Slow Filtration Speed:
It may be due to a couple of reasons. It does not necessarily mean you need new filters.Try these suggestions:
Air Pockets
If your Berkey filter isn’t working early on, the slow flow rate is likely caused by air pockets. Air pockets occur when the filters have not been fully primed and pockets of air have not been forced out of the filters by water during the priming process. The solution is to prime your Black Berkey Filter, or use an anti-airlock clip.
Partially Filling the Berkey
Each time you fill up your Berkey with water, it’s important to fill up your Berkey all the way to the top. It allows the filters to wear out evenly instead of the bottom of the filter doing most of the work, causing the filtration system to run more slowly and the flow rate to go down. To avoid overflow, check the bottom chamber first to ensure it is empty, then refill.
Turbidity and Sediment Clogging Micropores
Over time, turbidity and sediment can build up in your filter. To alleviate this, simply remove the elements and under running water, scrub the Black Berkey filters with a Scotch Brite pad. Within minutes, the filters will be good as new.
Typically, each Black Berkey Filter Element lasts approximately 3,000 gallons. We recommend replacing a pair of filters at 6,000 gallons of use. It can also be cleaned up to 100 times, which is why the filters last so long.