I use 5 drops of chlorine in each 16 oz water bottle, allow it to stand for at least an hour... that's where a two water bottle belt pack comes in handy. I add a couple more drops depending on how clear the water is.<br> I also pay attention to the type of bottom the river has... sand or rock is prefered, if it has a muck or a lot of vegitation I add a couple more drops.. but never more than a total of 8 per bottle.<br><br>For camp water I use a collapsable jug and add 16 to 20 drops per gallon... again let it stand for at least an hour before use.<br>This seems to work quite well, our group has never had any problems with sickness on our trips, the only complaint is the pool water taste... which you get use to after a day or so.<br><br>One trick I learned was to pour the water back and forth between containers an let it stand a few minutes before drinking... seems to release some of the chlorine to improve the taste.<br>