A water filter is a key piece of gear on nearly any backpacking trip. Many of these filters using a pump which moves the water through the filter and into your bottle. This design has its drawbacks as it may take a good amount of time and effort to pump all the water that you need for cooking, cleaning, and drinking. There is also the potential for part of the pump mechanism to break, something which could force you to have to boil all your water, take the "Giardia Challenge", or just be thirsty for the rest of the trip.
In this Instructable I'll show you how to use your existing water filter as a gravity powered water filter. This setup will use gravity instead of you to "pump" the water, be lighter, and be less prone to failure as there are no moving parts!
http://www.instructables.com/id/Portable-Coffee-Filtering-Straw-for-outdoors-or-co/
i gave you credit for helping me think of this
thanks again
thanks for the idea