Do the Black Berkey Filters remove tannins?

Tannins are naturally occurring polyphenols that are brownish or yellowish in color. They are a bitter-tasting substance commonly found in plants, seeds, bark, wood, leaves and fruit skins. Tannins can end up in water when vegetation in the source water begins to decay and ferment. This typically occurs in shallow wells, lakes, swampy or marshy areas, and coastal areas. Tannins produce the dry taste in wine and are also used in ink manufacture and leather production. They are non harmful but may be aesthetically unpleasing. The manufacturer has not tested for the removal of tannins but in their experience, tannins are not removed by the filter.