Another option as well if you are looking at the cheapest option would be to add a Katadyn Carbon Cartridge on to a .2 micron filter if need be, the
main thing is to use a .2 micron or less filter with carbon.
http://www.rei.com/product/709006$11.95
[color:#FF6666][/color]
_________________________
Failure is not an option!
USMC Jungle Environmental Survival Training PI 1985