Whats the most cost- and weight-effective way to treat water while backpacking?
Have you tried the Aquira Frontier water filter yet? Also, what's the best way, that isn't too expensive or heavy, to treat water while backpacking? Claudia Asheville, North Carolina

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I cant say Ive used the Aquamira Frontier ($10; aquamira.com) yet, but its certainly worth a look. The device is simplicity itselfbasically, a straw with a filter attached. Unfurl the straw, stick it into a water bottle, and sip. The unit is billed as capable of removing nearly all giardia, cryptosporidium, and other nasties. Its not a purifierviruses and very small bacteria can get throughbut you could use it in conjunction with something such as MSR Sweetwater Purifier ($10; msrgear.com) for nearly total protection from water-borne badies.
Aquamira Frontier Filter

Drawbacks? Well, yes. Even Aquamira bills it as more of an emergency” filter, or as a backup to a larger filtering unit such as a Katadyn Pocket Filter ($229; katadyn.com). It also is limited to about 20 gallons of filtering. Enough for one person for a week, certainly. The other drawback with gadgets like this is that they tend to force you to sip,” rather than drink.”
My own preference is the MSR Miniworks EX ($85) which I find to be effective, sturdy, and easy to use. It does weigh nearly a pound, so thats an issue. But it can filter a lot of water in a fairly short period of time.
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