A small number of customers have reported that their water (which was clear before filtering) appeared cloudy after filtering it through Berkey® systems equipped with Black Berkey® Elements, and in conjunction, some experience a very slow flow rate.

NMCL sells a large number of Berkey® systems and replacement Black Berkey® Elements globally each year, yet isolated reports of water cloudiness have come to us from a small handful of cities in North America. The largest number of instances have been from the Vancouver, British Columbia, Canada area.

Regarding the customer-reported issues:

  • Water cloudiness: in an effort to investigate these claims, NMCL conducted simple performance tests in three different states spread out across the US (from 3 different water sources) using some of the customers’ filters in question that produced cloudy water for them. NMCL was not able to replicate customers’ claims of cloudy water.

  • An associated slow flow rate: many of the filters associated with reports of cloudy water also had a slow flow rate (or in some cases, flow was stopped altogether). In several sets of filters reporting both issues from the Vancouver area, an unidentified film of particles was observed on the exterior of the filters that accumulated there during the short use of them by the customers. We installed the filters in a system and verified that they were slow flowing. However, after scrubbing the film off with a Scotch-Brite® pad, re-priming the filters, and reinstalling them in a Berkey® system, the filters performed as expected, providing clear water with an acceptable flow rate.

NMCL did not conduct testing to identify what may have coated the filters or contributed to cloudy water or slow system flow.

Potential Causes
Black Berkey® Elements are designed to filter water by reducing contaminants without introducing harmful contaminants into the water. A very small amount of media process dust is expelled during the initial priming process. Hence, the quality, appearance and taste of the water improves as it passes through the Black Berkey® Elements after they have been sufficiently primed. The reported instances of cloudiness may be caused by any number of reasons, such as insufficient priming. Alternatively, some water sources can be highly acidic and have high levels of dissolved minerals, including salts, or other substances (that may be unfamiliar to us). Black Berkey® Elements typically increase the pH of the filtered water, which can cause the “good minerals” to precipitate and come out of suspension in a natural process called flocculation, which makes them visible to the naked eye. In addition, temperature and microscopic air bubbles present in water can cause it to take on a milky appearance that dissipates over time. Lastly, perhaps there is a new or unknown substance or contaminant in the water that is affecting the chemistry of the water during the filtration process that produces the cloudy water effect. Again, these are just possibilities—we don’t know for sure. What does make sense is that the water should be cleaner after being filtered through Black Berkey® Elements despite the cloudy appearance of the water.

Cloudy water coming out of Black Berkey® Elements is very rare. The reported rate of Black Berkey® Elements producing cloudiness in their water is extremely small at approximately .0001% (far less than 1%). Given that NMCL was not able to replicate the reported issues, which occurred in an extremely limited number of geographic areas, we can only conclude that the issues are related to something found in the individual water supplies serving those areas. Berkey® systems equipped with Black Berkey® Elements are powerful and reliable. They have been tested by several independent third-party labs to address 200+ typical contaminants in freshwater sources. Those are just some of the many reasons that families facing natural disasters, missionary organizations working in unforgiving parts of the world, relief agencies battling the elements, and everyday families rely on Berkey® systems to do what they say they can do—and continue to choose them time and again.

Yet, as powerful and reliable as our systems are, we do acknowledge that a Berkey® system may not be the best solution for a very small number of customers due to the nature of their specific local water supply.

In the unlikely event that you experience the issues listed above, more frequent cleaning and priming of the Black Berkey® Elements and systems will likely restore any reduced system performance. Another solution may be to re-filter the cloudy water through your system by drawing off the cloudy water from the lower chamber and pouring it back into the upper chamber. Your Berkey® system will likely remove any precipitated or flocculated minerals during the second filtering process. Cloudy water or slower flow is not necessarily an indication of an issue with your Black Berkey® Elements or Berkey® system.

Simple Test to See if Local Water is the Cause
Purchase 2-3 gallons (or however much water your Berkey® system is designed to hold) of natural spring water, making sure to use a brand that is not sourced from your area. If necessary, disassemble your system and rinse the inside of its stainless steel chambers. Scrub your Black Berkey® Elements with a Scotch-Brite® pad (do not use soap). Re-prime and rinse off filters. Reinstall filters, then fill the upper chamber with natural spring water. Wait for water to completely drain into lower chamber. To evaluate the condition of the water processed by the filters, dispense some water from spigot into a clean, clear glass. If the water comes out clear, you can know positively that the issue is caused by something in your local water supply, and that your Berkey® system is operating as intended. In the unlikely event that the water still appears cloudy, please contact the Berkey® Water Systems Customer Support Team.

Black Berkey® Elements are covered by a limited pro-rated warranty; warranty terms and exclusions are listed at https://support.berkeywater.com/support/warranty-info/. If you have further questions about the performance of your system, please visit https://support.berkeywater.com/ for troubleshooting tips and more information.