i took this filter on a 5 day canoe trip...
i took this filter on a 5 day canoe trip in algonquin park ont. worked great for the first two uses then slowed to a drip. used what looked to be clear lake water, is thier a way to clean the filter in the field?
It's interesting that you had this experience, because with fairly clear water you should be able to filter much more water without having to clean the filter. However, I have had a similar experience. When I first got this filter, I was able to filter probably 30-40 gallons of murky water with little problem. However, I eventually replaced the filter, and on my last trip I had to clean it after only about 20 gallons of relatively clean water.
Yes, it can be cleaned in the field (without fully dissembling it). Drain the water, turn it inside out, and then take the mesh off of the filter and clean it (there is a tubular netting that slips off of the filter and allows you to unwind the mesh). Then, I put the filter in the water and (underwater) scrub it with a sponge or clothe. This can improve the flow for a while.
One other trick I have found is that if the filter begins to slow down, with the bag still full of water I will pinch the bag and 'rub' the filter through the bag. This usually speeds up flow for a little while.
When this filter works, it works great. However, I am always sure to have another filter (or water purification method) just in case.