How to test Black Berkey filters with red dye food coloring

Black Berkey Red Dye Food Coloring Test – Does it Work or Not?

How to test Black Berkey filters with red dye food coloring

I have heard conflicting reports about the validity of the “red dye test” (food coloring) for the Black Berkey water filter elements.

Some have said that it’s a valid test to indicate or verify that the filter is still ‘good’. Others have said, no, it’s not an accurate method of determination.

I have the correct information for you:
The test is valid ONLY if you’re using the right kind of red dye!

This explains why there have been conflicting reports out there. The wrong dye vs. the right dye. Apparently it matters. Here’s more detail:

From one of the Berkey dealers:

“The RED food coloring MUST be ARTIFICIAL using reds FD&C 40 and/or 3.”

Apparently the test only works with this artificial red dye (versus “artificial-free”).

From the dealer:

“There are more and more “artificial-free” red food coloring dyes coming onto the market. This is great for our food consumption, but this type of dye will get through the filters and provide a false/inaccurate reading of a defective filter. We’re seeing this more and more with our customers who then think their filters are defective, when in fact they are NOT.”

The right food coloring for the Black Berkey filter test
McCormick Red Food Color, 1 fl oz


How To Do the Red Food Coloring Test on Black Berkey Filters

Instructions sourced from Berkey’s ‘mothership site’,
New Millennium Concepts, Ltd

I’ve paraphrased for more clarity:

1. Start with an empty system (upper and lower chamber) and remove any Berkey PF-2™ Fluoride and Arsenic Reduction Filters(if installed – Important!).

2. Place cups in the bottom chamber directly underneath where the filter elements drain. This will help isolate which filter may be exhausted and which is still purifying effectively.

3. With filter elements installed, fill the upper chamber with water and add 1 teaspoon of red food coloring for every gallon of water. Be sure the elements are lined up with the cups in the bottom chamber.

4. Allow the water to run through to the bottom chamber.

5. If the red food coloring is removed entirely, your purification system is working properly.

6. If the water in any of the cups is red or has a pinkish tinge, then that particular black filter is defective or exhausted.


How Often To Do The Red Dye Test

Berkey recommends this test be done upon first use.
After that, every three to six months.

The red food coloring test is designed only for the Black Berkey® Purification Elements. NOT for the ceramic or other filter elements that do not filter out food color.

Make sure the food coloring is RED. Red food coloring (unlike the other colors) doesn’t have any minerals, so the element recognizes it as contaminant.

Tip: After sufficient water has filtered into the capture-cups, and if no pink hue is evident, you don’t need the rest of the upper reservoir to filter through. Just dump it.


If it Fails the Test

Is the washer for the filter element stem inside the upper chamber and is the wing nut secured at the bottom? If the washer is on the outside of the chamber with the wing nut, you will not have a proper seal, which will cause your system to fail the test. Place the washer on the inside of the upper chamber and re-run the test.

Tip: Tighten the wing nuts snug only. Don’t over tighten (threads might strip).

Are the blocking plugs properly sealing the unused holes without elements? Are the plugs installed tight with a washer on each side? If the plugs are leaking, this will cause the system to fail the test. Tighten the plugs more securely and re run the test.


New Black Berkey Filters

Tip: How To Clean Berkey Water Filters

2 of these filter elements will purify 6,000 gallons of water:
Black Berkey replacement filters
Berkey Black Berkey Purification Elements, Pack of 2

Continue reading: The Smallest Berkey Countertop Tabletop Water Filter

Read more: Berkey: Black Filter Elements vs. White Ceramic

Related: 5 Berkey Accessories For Your Countertop Filter


  1. Thank you for this information Ken. My biggest concern was knowing if the cartridges were still filtering properly.

    1. Good point PG
      Maybe keeping one of those metal click counters by the filter and clicking it every time it gets refilled?
      Ive thought about this too, one suggestion was to just change the filters every 6 months, sorta costly but when you consider the clean water and what that is worth not too bad

      1. How often do you fill it? If you fill a 2 gallon unit once a day that’s about 700 gallons per year. A filter should last (under this “normal” usage) about 9-10 years. Keep track of the date you put in the new filter and check it after two or three years.

        1. Sorry all, had to chuckle a bit, I probably fill my Berkey probably once a week, so 2 gallons a week at 52 weeks, 100 gallons a year, So basically I’m good for 60 years??????
          Good thing I got 2 extra sets of filters huh?? hehehehe

          Thanks for the Info Ken, think I’ll do a test and see, just cause :-)

        2. Agree with Lauren here, have the same usage and clean everything every 6 months as I’m using city water although I’m located in the strategic “armpit” of Illinois as I’m surrounded by Chemical and Nuke plants… Using the city well water which according to their annual reports is safe with the EPA but I’m filtering it anyway…

  2. I still can not get a straight answer on where these filters are made….none of the packaging says made in the USA or anywhere for that matter.

      1. Hi Lauren, thanks for the prompt response….I must be missing it, where did you find it on their site? Thanks much! Julia

        1. Found it a couple places. On berkeywaterfilter, down at the bottom of the page is the “Made in the USA” Logo. Also on theberkey, on one of their pages it specifies the location of manufacture. At bigberkeywaterfilters, search for “USA.” It’s about 2/3 of the way down the page.

          All of those are dotcom. I have no idea why they aren’t more clear about that.

  3. On my 1st set I did the artificial red dye test after about three years. I cleaned the filters every 4 months or so. Did the test because the filters get slower at filtering. Even slow there was no dye in the filtered water. Cleaned them, let dry for 2 weeks, labeled and put away just in case. Installed new filters and the water filtered quicker. We have a Royal Berkey which is 3.25 gallons. Gets filled about once every day and a half. Mr. drinks a lot of water and I use it for cooking. Cats get Berkey water too! Have a Pur on the faucet for rinsing veggies and jars for my tinctures or freeze dried food etc. Our water is considered one of the worst in the state.

  4. I would like to copy many of the articles and print them out and file them in my prepper file box. This is one of those articles as well as the one on cleaning the filters.
    What would be the least complicated (meaning computer simple) for doing that?

    1. Skeezix;
      Easiest I have found is to do a “copy/Paste” to Word, than print.
      Please make sure not to edit out the Author, meaning Ken.

  5. OK. I found the copy thingy. Where do I go for paste. I am on an iPad.

  6. Skeezix;
    Sorry cant help you with an iPad, but is there an editor like Word or Note-pad on there that you can save from?

  7. We have “cera-grav” filter systems….made by Doulton. One in Kitchen and one in 2nd bath. BOTH hold about 2-3 gallons, and we fill them almost daily (kitchen,,,,bath twice per week depending on little people visiting)
    We clean the filters once per 6 months and they continue to filter just great after MANY years. Love these units.
    Also added a “main line” double filter system one charcoal and one ceramic to the incoming line from the well. GOOD CLEAN WATER.
    Ken, keep these articles coming. They are always useful, and I have to admit I regularly print your articles and add them to our Prepper Handbook!

  8. Someplace I read that the Black Berkey Elements don’t have any silver in them and therefore do not stop bacteria from growing in the elements. And that they should be replace much more often (3 to 6-months) then most people are doing.

    Does anyone know if this is true?

    If they don’t have any silver impregnated into them how do they not load up with nasty bacteria as the silver is a way to stop bacteria. And if its not in the filter elements it seems like a design flaw.

    PS: Not an attack on Berkey, I have numerous Black Berkey Elements. I’m just wondering about this.

    1. Chuck, interesting point. One for the Berkey folks. I guess if one wanted too they could add some colloidal silver to the upper chamber water. I don’t know how much though.

  9. Would most of the fine folks here at MSB recommend the Berkey systems over other filtering systems? Maybe it is apples to oranges but my friend is all about Seychelles. Not sure which way to go. Less $$ for the seychelle , but have to use my own receptical to keep the water.
    Help please!!

    1. Mad Fab,

      Way back when I bought my Berkey, I researched as much as possible before I purchased. Berkey was, hands down, the Cadillac at the time. I’ve seen nothing since to change my mind. Yes, they seem pricey (they ain’t gonna get no cheaper), but the longevity of their filters more than make up for thee initial cost. In contrast, my son keeps a Brita filter, not nearly as efficient in removing pathogens, just for his personal use. The replacement filters for it, while much cheaper each, costs several times more per year due to their limited life. I consider the Berkey System as a life time investment that pays for itself many times over, especially compared to buying purified water for drinking.

    2. Mad Fab
      Just my opinion, get what you can afford. There are many ways to improve on a water filtration system.
      Not having one, is not one of those ways.!!!!
      YouTube “water filtration”, many good ideas, although some of the videos are B@tS##t insane.

    3. Mad Fab;
      I own a Big Berkey for the house, and Sawyer Mini’s for the Go-Bags.
      If you decide to get the Berkey, please buy it through Ken’s Link.
      Yes it’s not cheep, but it’s a one-time purchase, tis a very good unit.

  10. Dennis, SMG, NRP,
    Thank you so very much for your feed back😉. It really sounds like Berkey is the way to go. Long term the money spent is cheaper than other products. Looks like the Berkey is for us. Thanks again so much.
    Peace to all

  11. PS
    Ordering from Ken’s site as we speak.
    Try to support him since he is supporting me thru his wonderful site.

  12. Open the spigot on my Royal Berkey, fill my glass and enjoy. No science needed.

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