sears used to call this machine a distiller but people kept thinking alcohol. they changed the name to purifier to remedy that perception.
it is, however, just a simple distiller. that is what purifies the water. they come with a little activated charcoal filter to "improve the taste" of the water. it is not necessary except for those who dont clean their units regularly. you how people can be.
well, the filter actually recontaminates your water. it is simply unnecessary. dont ever use it and you wont have to buy another, either. like i said, i scrup mine with a dedicated scotch pad that does nothing else. i clean it with tap water only and just scrub the film out each time i use it. its quick and easy and prevents using the vinegar so often. dont buy any cleaner for it either. use the cheapest white vinegar you can find. works great. the buildup will occur mostly on the bottom. just let a little vinegar set in there while at work. it will be clean as new when you get back home. the scrubbing keeps the sides fairly clean, but once in a while you will have to fill it with hot water and vinegar and let it set. the acid in the vinegar does all the work. that stuff hardened on there is what would be hardening your arteries later on. that wouldnt be a problem if you could soak your veins in vinegar. instead, they have to stay at just above 7 pH or you will die. see the problem? fix the problem. you made a very wise decision for life.