The media used in our Fluoride filter elements can contain a small amount of harmless process dust or fines, due primarily to assembly, handling and shipping of these elements. For aesthetic reasons, we recommend the Berkey Post Filter elements be primed to remove the majority of this process dust, prior to installing these elements in your Berkey system.
If the Berkey Post Filter elements are not primed prior to use, the possibility of turbidity in the first few cycles of water may occur. For the sake of simplicity, turbidity appears as cloudiness in the water. In other words, the process dust/fines are what cause the cloudiness. For example, manufacturer had the Fluoride filter elements tested to determine at what level the turbidity falls off. The results were as expected.
The laboratory tested the turbidity remaining after priming the Berkey Fluoride Filter elements (as described in the assembly instructions). The results show that the levels of turbidity drop off dramatically if the priming process is followed. It is recommended that the Fluoride filter elements be primed for approximately 30 seconds in each direction, prior to installation.
For those purists, this priming process can be repeated an additional one or two times before installation. Our lab tests determined that the turbidity drops off as follows: One priming: Turbidity reduced by >94% Two primings: Turbidity reduced by >96% Three primings: Turbidity reduced by >98% The turbidity will continue to decline with each refill cycle of your Berkey system. While turbidity may be aesthetically unpleasing, according to current research, there are no negative health effects with which to be concerned.