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Black Berkey® FAQS

What is the shelf life of the Black Berkey® purification elements?
The shelf life of the Black Berkey® elements is indefinite.  In other words they will last until you need them.  We would advise however, if you intend to store them for a long period of time, that you store them in a zip-lock bag.  This is because they are powerful enough to absorb contaminants from the air, which could reduce their expected life if you have a lot of airborne contaminants in the area in which they are being stored.  A zip-lock back will prevent the above from occurring. 

Exceeds purification standards:
MS2 . Fr Coliphage

Exceeds purification standards:
E. coli - Klebsiella - Pseudomonas Aeruginosa - Giardia - Cryptosporidium - Raoultella Terrigena

TRIHALOMETHANES removed to below detectable limits:
Health effects: muscle & nervous system disorders, cancer
Bromodichloromethane - Bromoform - Chloroform - Dibromochloromethane

RADIOLOGICALS removed to below detectable limits:
Radon 222

INORGANIC MINERALS removed to below detectable limits:

Chlorine Residual
cancer, birth defects

Volatile Organic Compounds (VOCs)
Removed to below detectable limits

Carbon Tetrachloride
1, 1-Dichloroethane
1, 2-Dichloroethane
1, 1-Dichloroethylene
cis-1, 2-Dichloroethylene
1, 2-Dichloropropane

Ethylene Dibromide (EDB)
Heptachlor Epoxide
Lindane, Methoxychlor
2,4,5-TP (Silvex)


HEAVY METALS reduced by up to 95%:


nervous system damage


nervous system disorders


nervous system disorders


kidney damage


liver, kidney, circulatory system disorders


gastro-enteric diseases

rust, silt, sediment, foul taste and odors.

Concerned about Fluroide
or Arsenic in your water?

Click Here for more information
on reducing Fluoride and Arsenic
in your water with our PF-2
post reduction elements.

No need for expensive disposable filters.
Black Berkey® purification elements
are re-cleanable. When the flow rate decreases simply brush the Black Berkey® purification elements with a ScotchBrite® pad under running water, reinstall and your system is again ready to purify water. Each durable and efficient purification element will last for up to 3,000 gallons
6,000 gallons per set of two) and provide
years of efficient water purification.
What's more, the unique Black Berkey®
purification elements are self-sterilizing.

The Black Berkey® purification element
has been tested by State & EPA
accredited laboratories to exceed
EPA & ANSI/NSF (Std. 53) protocol.


How often do the Black Berkey® purification elements need to be replaced?
Each element has an expected life of 3,000 gallons or 6,000 gallons for a set of two.

I have been using my system for about six months and the flow rate has slowed down considerably.  Do I need to replace the elements?
No, unlike other filtration elements Black Berkey® purification elements are re-cleanable. What typically causes the filters to drip slowly is turbidity and sediment clogging the micro-pores of the purification elements. Simply remove the elements from your system, scrub the exterior of each element with preferably a white ScotchBrite pad or stiff toothbrush. Simply scrub a section of the filter until you see a bit of black on the white pad then move to the next section.  It’s simple to do and takes less than a minute. Then re-prime each element and reinstall them. Your problem should now be fixed.

How do I know when it is time to replace the elements in my system?
The best way to gauge when to replace the filters is to do the following:

  1. Multiply the number of filters in your system by 3,000 gallons to get Total Gallons For All Filters within the system.
  2. Next keep a track of how many times you need to refill the upper chamber in one week. 
  3. 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
  4. 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.
  5. Next calculate the future date for replacement (52 weeks per year) and write that date on a sticker and attach it to the bottom of your system for future reference.

By the way, if you have been using your system for some time now, you can still use the above formula to determine when to replace the elements. Just count forward from the date you purchased your system.

I will soon be leaving the country. Is there a way to test my Berkey® system to make sure it is working properly?
Yes, anytime you plan on taking your system out of the country we advise that you always perform the following test prior to leaving. You should test your filters by filling the upper chamber with water then add a tablespoon of red food coloring for every gallon of water within your upper chamber. If the red food coloring is removed entirely, your filtration system is working properly. If not, check to make sure that the wing nuts on your elements are securely tightened then re-run the test.

By the way, always prime new purification elements before leaving the country, as you may not have enough water pressure to be able to prime the elements at your destination.

I just purchased a Berkey® system but the system 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 being purged from the micro pores of the new purification elements.  Included with your Black Berkey® elements is a priming button and instructions for use.  Please remove and prime your purification elements, reinstall them and that should fix the problem.

I just purchased a Berkey® system but didn't receive a priming button. 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® purification elements. The box should contain two (2) elements. Attached to each element should be a rubber washer and a wing nut. Also in the boxes should be what could looks like another single black rubber washer. This is your priming button. It is thicker than the washer and the center hole is smaller. This black priming button can easily be confused with a washer; so we asked the manufacturer to change the color of the priming button back to tan.

Priming set-up

Priming your purification elements

Priming your purification elements diagram

How do I prime the Black Berkey® Purification Elements when water pressure is unavailable?
The micro pores on the Black Berkey® purification elements are extremely small, in fact they are small enough to filter red food coloring out of water. The benefit from having such extremely small pores is greater efficiency at removing pathogenic bacteria and other contaminates. The downside is that too much water tension can require that the purification elements be primed before they will flow properly. When you receive the purification elements, they are dry and air is trapped within the tiny micro fine pores. In certain parts of the world, water has more water tension than in other places and this can change from season to season. The higher the water tension, the more difficult it is for the water to force the air out of the micro fine pores using gravity alone. The pores that have air trapped within them do not allow water to pass through and therefore become an inaccessible passage for the water. This then causes the system to either filter very slowly or not at all.

Before traveling to and using the system in an area without water pressure we recommend that the purification elements be primed using the priming button. If this however is not possible and water pressure is not available to use the priming button method, the elements can be primed approximately 50% by using the below method. In other words using this method, the elements will not purify as fast as they will by using the priming button method however they will run significantly faster than if the elements have not been primed at all. The alternate priming method is as follows:

STEP 1: If your system is assembled, remove the purification elements from the upper chamber. Next, fill the lower chamber with water, then place the purification elements into the water in the lower chamber, upside down with the stems facing upward, and put a ceramic coffee cup (or something else that will hold them under the water) on top of each purification element stem to force the element down under the water. Let the purification elements soak in the water for several hours. This will force some of the air out of the stubborn pores. NOTE: Make sure that opening in the stems of the purification elements are not underwater as we want the water to be forced through the pores rather than entering through the hole in the stem.

STEP 2: The inside of the purification elements should now be full of water and significantly heavier. Try to keep as much water on the inside of the purification elements as is possible as you reassemble the purification element into the upper chamber by keeping the stems facing upward. Empty the water from the lower chamber and place the upper chamber back onto the lower chamber. Immediately fill the upper chamber with water.

When the purification elements have water within the bore (inside core), more force is generated to draw water through the purification element. This is because the water that drips out of the purification elements also hydraulically pulls new water into the purification element as the purification element begins to work like a siphon. Thus, in addition to the "Push" of gravity, there is also a hydraulic "pull" and this drastically improves the ability of the water to force the air from the micro pores. The above method is less efficient than priming the purification elements with the priming button but should be about 75-80% effective in clearing the blocked micro pores.

Let the water in the lower chamber run to waste and refill the upper chamber with water. Your Black Berkey® elements are now primed and ready for use.

What is the Micron Rating of the Black Berkey® purification elements?
With respect to the micron rating, we do not use or publish a micron rating for the Black Berkey® elements for the following reasons.

There is much confusion with respect to nominal and absolute micron ratings. An absolute micron rating is one that states the maximum pore size expected within an element.  The nominal micron rating is the average pore size within the element. This means that if 90% of the pores are .02 microns and ten percent are 2 microns, one could claim the nominal micron rating as .2 microns, which would imply that pathogenic bacteria and parasites would be totally removed.  But in reality the bulk of the water would channel through the larger 2-micron pores and thereby allow both bacteria and parasites to pass through. Therefore a nominal micron-rating claim can be very misleading.

With respect to the absolute micron rating, there is also confusion because there are two different standards to determine absolute; in the US the standard is 99.9% removal, but the international standard in 99.99% removal or 10 times greater removal. 

Clever marketers of products can use the confusion over the above differences to make product "A" appear to be better than product "B" when product B may be far superior in reality. For example, we used to report an absolute rating using the international standard because we have a large international customer base.  Several years ago we published a rating on our ceramic filters.  A particular company began to publish that our elements were .9 microns whereas theirs were .2 microns. However, our micron rating was based on absolute (international) while theirs was based on a nominal(US)rating.  When tested at Spectrum Labs, it was found that at the .2 to .3 microns range our filter removed more particulate than the other brand. Unfortunately many people make there purchasing decisions based on a micron rating that can be legitimately distorted and to a significant degree.

We soon became weary of trying to explain the above to our customers and so we decided not to participate any longer in publishing a micron rating.  Rather, we think an absolute pathogenic bacteria removal rate is a far better gauge because it is far more difficult to abuse.  Based on that criterion, the Black Berkey® elements remove greater than 99.9999999% of pathogenic bacteria such as E.coli. To our knowledge, no other personal filtration element can match that capability. In fact, the Black Berkey® elements are so powerful, they are unique in their ability to mechanically remove red food coloring from water.

It is time for me to replace my filter elements but I have a different brand name of gravity filter. Will the Black Berkey® elements fit my system?
Yes the Black Berkey® purification elements are interchangeable with other gravity systems and the PF-2 filters can be used as well.

The water in the upper chamber of my Berkey® system does not drain all the way. Is this normal?
Yes it is normal and not unusual for the last 1/2" to 1" of water to remain in the upper chamber.  By design the water must pass through very fine micro pores within the elements in order to pass from the upper chamber to the lower.  The lower the water level in the upper chamber, the lower the pressure available to force the water through the micro pores.  You might have noticed that the system purifies much faster when full than when half full.  That is because there is more pressure.  The only way to remedy the problem would be to enlarge the pores within the filter elements.  That would of course, reduce the efficiency of the purification elements.  During each cycle the water left from the previous cycle mixes with the water from the current cycle and is then purified.  You should not be concerned about the excess water during normal use however if you discontinue using your filter for a period of time such as during a vacation, it would not hurt to empty the upper chamber before departing.

It appears that there is a slight dimple in one of my Black Berkey® elements, is this filter flawed?
No, the Black Berkey® purification elements are about twice as thick as are standard gravity filter elements.  This is a built in redundancy or overkill, if you will.  The minor dimple in the filter should not cause any decrease in the elements efficiency.  However to check its performance, make sure the wing nuts are on tight and do the following:

Test your filters by filling the upper chamber with water then add a tablespoon of red food coloring for every gallon of water within your upper chamber. If the red food coloring is removed entirely, your elements are working properly. If not, check to make sure that the wing nuts on your elements are securely tightened then re-run the test.

I have found that when I boil the water or freeze it into ice cubes, I sometimes get little white floating things in the water.  What is this?
With respect to the little white floaters in the water, it is not bacteria but rather a problem that sometimes occurs with hard (heavily mineralized) water. When water is filtered through your system, the Black Berkey® purification elements actually increase the PH of the water.  This is healthful as Pathogenic bacteria and viruses thrive in acidic environments and conversely have difficulty surviving in alkaline environments.  This is also true inside your body.  When the PH level of the purified water is raised, the acidity of the water goes down and the water is no longer able to hold as many minerals in solution.  When this happens the minerals begin to precipitate out over time and depending on the mineral composition they will either sink to the bottom or float to the top.  This process is known as flocculation and the precipitated minerals are usually referred to as "white floaters".  The bottom line is that this is nothing to be concerned about, the white floaters are minerals that were already in your water; they are now simply visible whereas they were previously invisible due to their suspension in an ionic form.

What are the Black Berkey® elements made out of and how do they work?
Without getting too complex, several methodologies are utilized by the Black Berkey® purification elements.  The elements are composed of a formulation of more than a half dozen different media types constructed into a very fine matrix creating millions of micro-fine pores.  The pores are so small that pathogenic bacteria, cysts, parasites, sediment and sedimentary minerals are not able to pass through them. The media formulation both "absorbs" some contaminates and "adsorbs" other contaminates.  Next, heavy metals ions (mineral molecules) are extracted through an Ion exchange process where they are essentially electrically bonded to the media. Finally, our filter elements are designed such that each water molecule can take several minutes to pass through the filter elements whereas these molecules passing through other filtration systems pass through those filters in literally microseconds.  The longer the water molecules are in contact with any media, the greater the removal of the various contaminates.

I did a TDS reading on the purified water and was surprised to find that the reading was about the same with the purified water as it was with the unpurified water. Is my system working properly?
Yes, a TDS meter measures only Total Dissolved Solids or minerals; dissolved solids are simply dissolved minerals in an ionic form.  A TDS meter does not measure the amount of biological and chemical contaminates.  Black Berkey® elements are designed to leave in your water the healthful and beneficial minerals and to extract only the unwanted heavy metals such as lead and mercury as well as sedimentary minerals such as iron oxide and aluminum.  Therefore, your TDS reading will not change much unless you have a significant amount of heavy metals or sedimentary minerals in your water.