Originally posted by Colt:
I would expect it to last a long time filtering water from city plumbing. But how long will it last with rainwater collected from an asphalt roof? Or, water you dip from a ditch, or a neighbors mucky old swimming pool?
I haven't had to use mine under field conditions yet, but I suspect the filters will last not quite as long, and it will take it longer to filter the water. With tap water, I can filter over a gallon an hour. Keeping in mind that we need a minimum of two gallons of water per person, per day, to maintain our health--and the fact that I don't want to filter water 24 hours a day in an emergency--explains why I bought two.
If you're using it for anything other than tap water, I would definitely pre-filter your water before running it through the Berky. There are a number of ways to do this. Directions for a pre-filter I used in Chad a long, long time ago can be found here:
Family Preparedness: Water Onward and upward,
airforce
