There are 3 factors to consider when choosing the best size for your needs:
- How many gallons of water do you consume per day? According to research conducted by the USDA a person should consume 30ml of water per kg of body weight per day. The average man weighs 70 kg (154 lbs.) and the average woman weighs 61 kg (135 lbs.) so lets us 66 kg. 66kg x 30ml = 198ml or about 1/2 a gallon of water per person per day. Which is why you hear to drink 8 - 8oz. glasses of water per day. 8x8=64oz. exactly 1/2 a gallon. Persons who are very active or elderly should consume more. The 1/2 gallon of water per person per day rule is the water you need just for drinking.
Most of our customers find that once they start using their system they also like to use the filtered water for cooking. Cooking with water from your Berkey water filter basically doubles your use to 1 gallon of water per person per day. We at Berkey filters have found that after many years of customer feedback that this is the number you should use 1 gallon of water per person per day.
- What is the holding capacity of the system? The larger the holding capacity of the system the more reserve use you will have. For example: if you had a Travel Berkey (holds 1.5 Gal.) and While you were cooking dinner on a hot day your children came in the house after being outside with their friends and together they drank 6- 8 oz glasses of water (.4 Gal.). You need to make iced tea ( 1 Gal.) and you need water to boil pasta ( 1 gal.) that is a total of 2.4 gallons. Your travel Berkey only holds 1.5 gallons. You want to make sure the system you choose holds enough water for your peak needs.
SYSTEM HOLDING CAPACITY Travel Berkey 1.5 Gallons
Big Berkey 2.25 Gallons
Berkey Light 2.75 Gallons
Royal Berkey 3.25 Gallons
Imperial Berkey 4.5 Gallons
Crown Berkey 6 Gallons
- What is the flow rate of the system? The more filters your unit has, the faster your unit will produce water and the faster it will recover from peak or sustained water needs. The taller the system the more water pressure that will generated also increasing the flow rate. The numbers shown on the chart below are when the unit is completely full. The flow rate will decrease as the level of water in the upper chamber falls.
SYSTEM FLOW per hour With maximum # of filters Travel Berkey 2.75 Gallons
2.75 Gallons
Berkey Light 4.25 Gallons
4.25 Gallons
Big Berkey 3.5 Gallons
7 Gallons
Royal Berkey 4.0 Gallons
8 Gallons
Imperial Berkey 5.5 Gallons
16.5 Gallons
Crown Berkey 6.5 Gallons
26 Gallons
What size Berkey water filter system would be best for my needs? After years of customer feedback and field testing Berkey filters found that if you take the flow rate of the system and multiply that by the holding capacity, this number is a good indicator of the maximum number of people that each system would support under normal conditions. If you feel the your water needs are more than normal or if you plan on using the water filter for anything other than drinking and cooking, we suggest that you purchase the next size larger system than indicated on the chart below.
Berkey Comparison Chart
System Holding Capacity (Gals.)
Flow Rate (GPH)
Maximum # of people
Travel Berkey 1.5
2.75
4
Berkey Light 2.75
4.25
11
Big Berkey w/ 2 Filters 2.25
3.5
8
Big Berkey w/ 4 Filters 2.25
7
15
Royal Berkey w/ 2 Filters 3.25
4
13
Royal Berkey w/ 4 Filters 3.25
8
26
Imperial Berkey w/ 2 Filters 4.5
5.5
25
Imperial Berkey w/ 4 Filters 4.5
11
50
Imperial Berkey w/ 6 Filters 4.5
16.5
75
Crown Berkey w/ 2 Filters 6
6.5
40
Crown Berkey w/ 4 Filters 6
13
80
Crown Berkey w/ 6 Filters 6
19.5
120
Crown Berkey w/ 8 Filters 6
26
150
How do I know when it is time to replace Black Berkey elements in my system?
The manufacturer suggests 2 methods. The first method is:
- Multiply the number of Black Berkey elements in your system by 2,000 gallons to get Total Gallons for all Elements within the system.
- Next keep track of how many times you usually refill the upper chamber in a week.
- Then multiply that figure times the capacity in gallons of your particular system (for example the Berkey Light system is 2.75 gallons) to determine Total Gallons Used per Week.
- Finally divide the Total Gallons Used per Week into the Total Gallons for all Filters and that will tell you how many weeks before the filters should be replaced.
- Next, calculate the future date for replacement (52 weeks per year), write that date on a sticker and attach it to the bottom of your system for future reference.
Your Black Berkey elements will never stop working; the filtration rate just slows down. This brings us to the second method. If after cleaning your elements they do not filter any faster; it is time to replace them. This is the simplest way to decide, and the one we use ourselves.
We are on well water. Do we need the PF-2 elements?
No. The PF-2 elements should only be used if: ...you are on city water...you have confirmed with your city that they are adding fluoride to the water...you want to remove the fluoride. The PF-2 elements are not needed if you are on spring water.
What are the basic differences between the Berkey Light and the other stainless steel systems?
The Berkey Light system is designed for outdoor use therefore it is about three pounds lighter in weight than the equivalent capacity of our stainless steel system. The Travel Berkey system is also designed for outdoor use and is the smallest of the stainless steel systems. It is compact enough to fit within a suitcase because unlike the Berkey Light system, the upper chamber nests within the lower chamber during travel. This is the preferred system when mobility is a big issue.
The four-multi use systems are designed for indoor everyday use so they are of a heavier construction than the above systems but these systems can also be used outdoors or during unexpected emergencies when a source of potable water may not be available.
I have been using my system for about 6 months and the flow rate has slowed down considerably. Do I need to replace the elements?
No. Unlike other filtration elements, the Black Berkey elements and the ceramic elements are re-cleanable. What typically causes the filters to drip slowly is turbidity and sediment clogging the micro-pores of the elements. Simply remove the elements from your system, scrub the exterior of each element under running water with preferably a green pad (3M or ScotchBrite brand, etc.) or stiff toothbrush. It’s simple to do and takes less than a minute per element.
Many news stations have reported that pharmaceuticals have been found in the water of many cities in the U.S. Do the Black Berkey elements remove drugs from the water?
There are simply too many varieties of pharmaceuticals that a water filtering system could be tested for to see how it performs. By too many I mean it is impossible to test for them all. However, we do know from testing, that the purification process used by the Black Berkey elements remove more pollutants than any other system available on the market today. In other words, if there are any systems that remove pharmaceuticals from the water, the Black Berkeys are one of them.
I just started using my Berkey system but it is hardly filtering any water at all. Am I doing something wrong?
Typically the problem you are experiencing is due to high water tension, which prevents the air from purging from the micro pores of the new purification elements. Included with your Black Berkey elements is a priming button and instructions for use. Take out the Black Berkey elements, prime, and re-install them when you finish.
Is there a way to test my Berkey system to make sure it is working properly?
Yes. You can test the Black Berkey elements by filling the upper chamber with water, and then adding a tablespoon of food coloring for every gallon of water within your upper chamber. If the food coloring is removed entirely, your system is working properly. If not, make sure the wing nuts on the elements are securely tightened then re-run the test.
I just purchased a Berkey system but didn't receive a priming button with my Black Berkey elements. Instead, I think I received an extra black washer in the box. The instructions say to use the tan colored priming button. What gives?
Please check in the box which held your Black Berkey elements. The box should contain two elements. Attached to each element should be a rubber washer and a wing nut. Also in the box, should be what could look like another single black rubber washer. This is your priming button. It is thicker than the washers and the center hole is smaller. This black priming button can easily be confused with a washer (we asked the manufacturer to change the color of the priming button back to tan).
Do the PF-2 elements replace the Black Berkey elements?
No. The Black Berkey elements and the PF-2 elements are used together at the same time. The top of the PF-2 elements screw onto the bottom of the Black Berkey elements (similar to installing a light bulb). The water flows through the Black Berkey elements, then the PF-2 elements. "PF" in PF-2 stands for Post Filter.
We are on well water. Do we need the PF-2 elements?
No. The PF-2 elements should only be used if: ...you are on city water...you have confirmed with your city that they are adding fluoride to the water...you want to remove the fluoride. The PF-2 elements are not needed if you are using spring or well water.
Keep in mind that use of the PF-2 elements slows the filtration rate of your Berkey system by 15 – 20 %. They also displace water which means your Berkey system will hold (store) less water in the bottom chamber.
I installed my PF-2 elements but my water is a bit cloudy, and why does it have a bad taste?
Insufficient re-conditioning (priming) may result in an undesirable taste and/or cloudiness in the water. The odd taste is from process dust that may not have been washed free from the elements during the conditioning process. Please remove the PF-2 elements and re-condition them for no less than 60 seconds (longer may be needed) on both ends. This should expel any residual process dust and fix the problem.
Can I filter sea (salt) water through my Berkey system?
No. The concentration of salt in sea water will more than likely ruin the elements fairly quickly.
I have a water softener installed in our house, can I filter that water through my Berkey?
Some folks do but we do not recommend it. It is best if you put water in your Berkey that has not gone through your water softener (the excess salt will likely shorten the life of the elements).
In case of an emergency, can I take water from our pool and filter it with my Berkey system? Will all the chlorine be removed?
Yes. The Berkeys can make chlorinated pool water safe for consumption. However, keep in mind that such a use will cause the elements to wear faster. So, I would only do so in case of emergency.
Which of the three methods of water filtration, reverse osmosis, distillation or Berkey purification is the healthiest for drinking purposes?
With respect to the healthfulness of the water, most health experts that are up to date on current research are no longer recommending drinking RO or distilled water on a long-term basis because these methods remove all the beneficial minerals from the water making the water an acidic "hypotonic" solution. A chemist will tell you that any time a hypotonic (de-mineralized) solution comes into contact with a "hypertonic" (mineralized) solution, the minerals within the hypertonic solution will transfer out and into the hypotonic solution until equilibrium is achieved. What this means is simply that when one drinks hypotonic water, the minerals in the blood and lymphatic system, which are hypertonic, transfer into the hypotonic RO or distilled water that is consumed and the minerals are flushed out of the body upon urination.
In an effort to re-mineralize, the blood and lymphatic systems then begin to scavenge for minerals from other parts of the body, such as bones and other organs, and this process repeats itself every time de-mineralized hypotonic water is re-consumed. Several studies suggest that people who drink de-mineralized water (hypotonic) over a long period of time tend to be more prone to degenerative diseases such as osteoporosis.
Berkey purification systems do not remove the beneficial minerals from the water but they do extract harmful heavy metals such as lead and mercury as well as sedimentary minerals such as iron oxide. Therefore, the TDS reading will not typically change much unless there are a lot of heavy metals or sedimentary minerals in the source water.
With respect to maintenance, how does reverse osmosis, distillation and Berkey systems compare?
All Berkey systems are easy to disassemble and clean. The lower chamber should be washed in ordinary dishwater occasionally. The elements may need to be cleaned typically after 6-12 months of use.
Distillation systems need to be soaked and cleaned with vinegar solution to remove the scale, typically after each gallon or two.
Reverse osmosis systems can have up to four filter elements, with each needing to be changed at differing intervals from four months up to two years. This requires that the water pressure be shut off and part or all of the system to be disassembled for maintenance. Additionally, the bladder tank should be washed with a chlorine solution at six-month intervals to kill any colonizing bacteria.
What is the pathological removal capability of a reverse osmosis system vs. the Berkeys?
Reverse Osmosis does not remove pathogenic bacteria and that is why it is often necessary to add an additional UV light to the system. However, the UV sometimes does not kill all the bacteria because any turbidity in the water can create shaded spots preventing some bacteria from being exposed. Typically, the UV is installed before the bladder tank; however it is in the bladder tank that bacteria usually colonize. Therefore, if the bladder tank is not sterilized on a regular basis, it becomes a source for bacteriological contamination that is never exposed to UV. Additionally, the carcasses of the dead bacteria remain within the drinking water with an RO system whereas they are removed by the Black Berkey elements.
With respect to cost, how does reverse osmosis, distillation and Berkey systems compare?
With respect to upfront cost, RO systems typically are the most expensive due to the cost of the system and the additional expense to have the system plumbed in. Next in cost would be a distillation unit. A Berkey system will typically be the least expensive of the three.
With respect to cost per gallon of water, calculated upon the cost per gallon for replacement filters and energy costs, distillation systems and RO systems properly maintained typically cost between 35-65 cents per gallon. A Berkey system typically costs about 1.6 cents per gallon.