NMCL’s most recent laboratory testing indicates that the Black Berkey Purification Elements will initially reduce Fluoride up to 99.9%. Typically, carbon-based elements that reduce Fluoride begin to lose that ability rather quickly. This may be the case with Black Berkey Elements as their efficiency at removing Fluoride likely plays out long before the 3,000-gallon life of the element. There are a number of filters on the market that utilize carbonized bone char (a media that NMCL purposely chooses not to use), and that make claims for Fluoride reduction, without informing their customers that the fluoride removing ability of the filters plays out quickly. The reason this occurs is because it takes a very large amount of media to remove small amounts of Fluoride. Therefore, there is not enough media in such filters to remove Fluoride effectively over the long term. For example, we have testing for a competitor’s 3-filter system that utilizes bone char for their Fluoride removal claims and, as one would expect, those elements become quickly exhausted. Testing shows that their efficiency declines from 100% removal to 81.4% removal after filtering a mere 45 gallons. This is equivalent to only 15 gallons per element required for them to experience a dramatic ~20% decline in efficiency. This same effect likely occurs with Black Berkey Elements after a few hundred gallons. For that reason NMCL developed a more durable and longer lasting solution for Fluoride reduction by creating the replaceable Berkey PF-2 Fluoride reduction elements. The media in a set of Berkey PF-2 elements can reliably remove Fluoride contaminants for up to 1,000 gallons, which is less than the 3,000 gallon life of the Black Berkey Elements but again, that is why they were designed to be replaceable. This enables the users to reliably remove Fluoride contaminants from their water while taking full advantage of the 3,000 gallon life of their Black Berkey Elements. The Black Berkey Purification Element’s job is to remove a wide variety of potential contaminants, while the Berkey PF-2 Post Filter’s job is to remove Fluoride contaminants that the Black Berkey Purification Elements may begin to miss after extended use. Actual capacity is dependent on the presence of other competing contaminants in the source water. High levels of arsenic and heavy metals may reduce the capacity and efficiency of these elements.