As a Boy Scout of ten years, I have considerable experience with water filters. When you go on a camping trip, I recommend taking extra parts for your filter. Always sterilize these parts at home before you go. Look at the directions for your particular filter before doing so. If you have extra spare parts, then you will be ready when you or a young child drops the part of the filter that goes in your water bottle into the water that is being sterilized. This way you can change out the parts, so you can remain sterile and keep pumping.
Another way this comes in handy is when you are filtering water with lots of silt in it. After a lot of use in this fashion, the filter can become clogged. This will make it more difficult to pump water. Your arm will tire out very fast if this is the case! With a spare on hand, you can just lock it right into place saving you a lot of effort and giving you more time to enjoy your trip.
