microfilter pumps/chlorine

[Mrs Baggins]

So....I have an MSR Sweetwater microfilter/pump. I'm leading a group of women on an overnight on the AT and a few of them have never been out overnight. One of them bought a Sweetwater on my recommendation, but she bought the $99 one that comes with a bottle of chlorine. She was confused because I never mentioned anything about that with my Sweetwater. To be honest, I didn't know that was even an option. It's been my experience that people use EITHER a microfilter pump OR chlorine, but usually not both. So....how many people do use both??? I've used only my Sweetwater for 3 years and I've never taken ill. Seems to me using that and chlorine is overkill......what say you? :confused:

[handlebar]

The chlorine is for viruses. Microfilter pumps filter cysts like giardia as well as bacteria, but viruses are too small to get through. The Sweetwater chlorine is actually a chlorine dioxide solution (same as created with the chemical reaction of part 1 and 2 of Aqua Mira) and that is a chemical used in municipal water treatment plants. Viruses usually aren't a concern in water sources in backcountry of USA, but might me in lesser developed countries or in water sources heavily contaminated by livestock.