This is slightly off the original topic, but you were asking if there was a light weight way to filter your water vs. using chemicals and dealing with crud in your water.
Like you, I am reluctant to just use chemicals and drink chunky water.
This is a copy of a review I posted on the Sawyer inline filter and how to build a gravity filter.
Here is a copy of it with 3 different ways to use the filter:
Pros: Light Weight, Field Cleanable by backwashing, No Chemicals, No Pumping
Cons: Setup time longer than traditional filter. Speed of filtration can vary based on conditions. Like traditional filters, susceptible to damage if frozen.
Warning: Do Not allow any type of filter to freeze. Drain completely when done. Sleep with filter in your sleeping bag, if necessary to prevent freezing. Alway carry water treatment chemicals as an emergency backup in the event your filter fails.
I now use the Sawyer inline filter as my sole water filtration system for my family and I, including my four year old daughter.
My first experience using the Sawyer inline filter was on a backpacking trip to Lake Vernon in May 2007 in Yosemite above Hetch Hetchy Reservoir.
Conditions were bad with rain turning to snow at the higher elevations. We were forced to retreat back half way into the trip when snow levels reached knee high levels and my wife had earlier fallen and injured her leg. We retreated to a area that had snow on the ground at levels of two or three inches, where we could pitch our tents.
Our only source of water was a small, stagnant pond that was choked with fallen trees and decaying grasses all along the shoreline. The water along the shoreline was shallow, green in color and choked with small bits of debris in the water.
In our group of four, only one of us had a traditional filter, a MSR Sweetwater Micro filter. After pumping about 3/4 of a Liter, the filter complete clogged up and failed. Unfortunately, the person who had brought the filter had forgotten to bring the cleaning kit for the filter!
I pulled the gravity filter out and assembled it, hoping that it would work as advertised. In my dirty water bag of green water, I could clearly see bits of dead grass and a few small bugs swimming around.
To my surprise, the filtered water still had a greenish, brown color to it. With some reservation and skepticism, we drank the water and cooked with it. What other option did we have? Thankfully, the filter worked and no one got sick during the remainder of the trip or afterwards.
I estimate that each one of us easily drank three to four liters of water filtered by the Sawyer inline filter.
Since that experience, the Sawyer filter has been the only filter that I use.
Recent trips with the Sawyer filter:
4 day, 50 mile loop from Yosemite's Glacier Point to Red Peak Pass at 10,800 ft to Merced Lake, Little Yosemite Valley, back to Glacier Point.
4 day, 70 mile trip on the High Sierra Trail from Crescent Meadow to the top of Mt. Whitney.
Here is the list of items that you will need:
* Sawyer In Line Filter 1.80 oz
* Platypus Filter Link 0.50 oz
* Platypus Water Tank 4 Liter 4.50 oz
* Platypus 2+ Liter Water Bottle 1.20 oz
* Nite Ize Figure 9 Rope Tightner Small Size 0.25 oz
* Kelty Triptease Guyline/Cord 3-4 ft. 0.10 oz
* 3ft. 3/8" Food Grade Vinyl Tubing 3.50 oz
* 2 3/8" Metal Grommets 0.25 oz
* Grommet Tool for installing grommets
Total Weight of Full System: 12.1 oz
Weight of Stripped Down System: 6.8 oz
(See Below for details)
Weight of Trail/Dayhiking System: 3.3 oz
(see Below for details)
How to Build Sawyer Gravity Filter:
1. Identify top and bottom of Sawyer Filter: Top of filter is the input for dirty water. Bottom is output for clean water
2. Attach Tubing included with Sawyer Filter to "top" of Sawyer Filter
3. Secure tubing to Filter with hose clamp included with Filter
4. Attach Platypus Filter Link to open end of tubing
5. Install one grommet at the left side of the bottom edge of the Platypus Water Tank
6. Install one grommet at the right side of the bottom edge of the Platypus Water Tank
Note: When the Water Tank is standing upright on a table the grommets should be facing towards you, not underneath the Water Tank. Grommets are for hanging Water Tank upside down using cord from a tree branch or tree trunk
How to use Sawyer Gravity Filter:
1. Fill Water Tank with Dirty Water
2. Seal "Zip Lock" top of Water Tank
3. Make sure that threaded cap included with Water Tank is tightly installed
4. Thread Cord through both grommets
5. Hang Water Tank upside down from a tree branch or tree trunk using Cord
6. Using Nite Ize Figure 9 Rope Tightener to quickly tie or untied cord to tree branch or tree trunk
7. Attach 3ft. 3/8" Food Grade Vinyl Tubing to the "bottom" of Sawyer Filter
8. Stand Platypus 2+ Liter Water Bottle Upright on the ground
9. Lift hanging Water Tank to upright position and remove threaded cap
10. Screw on Filter Link/Sawyer Filter to Water Tank
11. Lower Water Tank to the Hanging upside down position
12. Start filtering process by sucking on end of 3 ft. Food Grade Vinyl Tubing until water flows through filter
13. Insert end of 3ft. Food Grade Vinyl Tubing into Platypus 2+ Liter Water Bottle to collect clean, filtered water
14. When Platypus 2+ Liter Water Bottle is full replace with an optional second Water Bottle to filter remaining water in Water Tank
15. If you only have one Water Bottle, unscrew Filter Link/Sawyer Filter and thread cap onto Water Tank
16. Filter additional water as needed
Note: For additional convenience, a second Platypus Filter Link can be attached to the end of the 3ft. tubing and threaded to the Platypus 2+ Liter Water Bottle. If this is done, thread Filter Link loosely to allow air to escape from the 2+ Liter Water Bottle. Failure to do so will result in pressure accumulation in the Water Bottle and will slow or stop water flow to the Water Bottle.
Note: As you become more proficient at using the gravity filter, you can attach the Sawyer filter to the Water Tank before hanging the bag upside down from a tree.
How to save weight using Stripped Down System:
1. Only use Sawyer Filter, Platypus Filter Link, and Platypus Water Tank
2. Use your hydration system as your "catch bag" for clean water
3. Remove bite valve from hydration system
4. Connect bottom of Sawyer Filter to your hydration system's hose where bite valve was attached
5. Lay Water Tank on its side on a rock or fallen tree vs. hanging from a tree branch or tree trunk
Note: I use a Platypus 1.8 L Hoser Hydration System (3.5 oz), which has a gusseted bottom that allows it to stand upright.
When using the Hoser as a catch bag, it is important to loosen the threaded cap that connects the tubing to the hydration bag to prevent pressure accumulation, which will slow or stop the flow of water.
How to use Sawyer Filter on the Trail or Day hiking:
1. Only use Sawyer Filter, Platypus Filter Link and 1 oz. disposable 1 pint/500 ml water bottle
2. When hiking on the trail and you want a fast drink of water without having to use the full system, fill 1 pint bottle with dirty water
3. Screw on Filter Link/Sawyer Filter loosely to 1 pint bottle
4. Turn bottle upside down
5. Use bottom of Sawyer filter as a straw to suck water from bottle through filter
Note: Loosely thread the Filter Link/Sawyer Filter. As you drink water, you should see a steady stream of air bubbles rising in the bottle.
Threading the Filter too tightly to the bottle will create a vacuum as you drink, which will collapse/crush the bottle and slow the flow.
Seeing the air bubbles rising in the bottle is an indication that you have not threaded the Filter too tightly.
I hope that this helps you to lower your pack weight and help you to build a gravity filter using the Sawyer Inline filter.
Note: Regarding Backwashing filter to clean in the field.
I have not experienced a reduction in water flow while in the field.
Each time that I have returned from a trip I have backwashed the filter using the gravity filter system using a small cap full of bleach followed by rinsing the filter two times with clean water.
Based on my experience at home, I see no reason why I could not backwash the filter in the field.