
This invention relates to an ion exchange column for the removal of bacteria from a liquid medium wherein the column has, as an indicator to indicate when the column capacity for removal of bacteria is exhausted, a filter having submicron pores which will become plugged after a short period of usage with an exhausted bacteria-removing ion exchange column so that pressure build up will noticeably reduce the flow of liquid exiting from the filter thereby indicating to the user that the ion exchang...











