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I have a PUR Hiker Microfilter and a Katadyn Water Microfilter sitting in my closet that I only use once in a great while (I don't go on overnight backpacking trips very often).

Whenever I do plan on a trip, I'm always hesitant to trust these filters are still in good condition to use. Don't they develop mold or other contaminants when left idle for years? I'm talking like 5 or so years without use...

Is there a way to clean these so I can be sure they are safe to use, or does the microfilter cartridge have a certain shelf-life and is then no longer safe to use?


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1 Answer 1

up vote 7 down vote accepted

As I understand the technology, your microfilters will not expire on the shelf if maintained and stored properly. Their lifetime is determined by the number of gallons pumped.

What can happen is if you don't properly dry out your filter before storing then it will develop mold. In that situation you can decide if it is best to clean the filter or replace it. For cleaning instructions I copied the following from Katadyn's Q&A page:


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I would add that you can buy dye which you can use to test filters. You put the dye in water, pump, and if it comes through the filter... then it's no good. –  Russell Steen Feb 21 '13 at 2:12

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