I've been hiking and back packing some over the years. Recently I have been reading some of the books backpackers who have hiked the AT and PCT, that is the Appalachian Trail and the Pacific Crest Trail, have written. I find it amazing people use their water filters in such inefficient ways.
My kid brother and I took our first long distance back pack on Isle Royale in Lake Superior. My mother, who was a pretty awesome woman, took her two teenage children on a backpacking trip. I was a voracious reader and had read so many camping and backpacking books, I felt like an expert. That first day out of Rock Harbor we hiked three miles together. The second day, my mother couldn't carry her pack so I carried hers and mine. She took a boat back from that campsite, Daisy Farm. My brother and I packed everything we had thought we would need and now realized we didn't into our mothers pack and we set off across the island taking the Minong Ridge trail.
We had problems. Fuel conservation, water conservation, purifying water (boiling was the only way the rangers had told us back then), food supplies. Reading about these things and dealing with the reality of them was very different. Everyone talks about this, but, backpacking and parenting are things that really can't be prepared for well enough.
The reality is always different from what we imagine based on the theory.
Using a water filter sounds easy, drop the intake hose, maybe with a pre-filter into the water and pump away. That can work, but, it will kill your filter faster than it needs to die and that filter can be the difference between life and death. Quite literally. Also, it creates the potential to contaminate the exterior of the filter with something you don't want.
The first step in batch water treatment is to collect the water. Use a nylon bucket (like I do) or a gallon sized ziplock bag, or any lightweight, flexible container you can put more water into than the size of your largest water bottle.
The second step is clarification. Wait a while for the water to settle and then skim off the floaties. Now the water being pumped is relatively clear and your filter will thank you.
Third, use an inlet filter and pump the water in your water bag through your filter and into your water bottle.
Pretty simple, but...there is more.
Filtration removes most stuff, but, not everything. There are water filters and water purifiers. If you have a water purifier, like a First Need, the task is done. If not, we need to treat the water we have just pumped with a chemical disinfectant like iodine, halazone or chlorine bleach. Unscented chlorine laundry bleach, will do the trick.
If you need a sanitizer for your cooking and eating utensils, rinse out your water bag, fill it with water and add 25 drops per quart. Don't drink the water being used as sanitizer, that much bleach will make people sick. Because of the potential for cross contamination it is a good idea to occasionally sanitize water bottles and the outside of the water filter, hose and pump apparatus.
On Isle Royale my brother and I each carried two 32oz canteens. Not enough.
In my thirties when I was backpacking around Michigan using Jim DuFresne's guides I carried near two gallons of water. Two 64oz bottles in the bottom section of my pack. Two 48oz bottles in outside pockets of my pack. One 22oz bottle in a small water bottle pouch on my pack or on my belt. I used pre-measured, home made, heat sealed packets of Gatorade to add to my 22oz water bottle, 2 per day. It is amazing how helpful that is.
My brother and I first made them for our Isle Royale trip for our canteens using a gadget my mother had purchased. Now, they are packaged foods you can buy at a party store.
I also carry an emergency filter. It is little more than a thick straw, but, used properly it could be the difference between life and death.
I also carry a two ounce bottle of unscented chlorine bleach with one of those caps that has the little flip nozzle. I put it in a ziplock snack bag. Yeah, I could use iodine or halazone, but, bleach is cheaper and can be used to sanitize my gear.
I cannot stress how important good sanitation is when back packing. When you think you are being careful, be more careful. Be careful how and when you use the bleach. I usually dig a hole and dump it into the hole, then I cover the hole.