Originally Posted by
Casey & Gina
Backflushing is not an issue for me - if you look at the picture of my complete setup, I filter from a dirty bag into a clean bag. Then I transfer water from the clean bag into the bladder without taking it out of my pack via the use of quick disconnect fittings. Every time I have filtered adequate water, before disconnecting the clean bag from the filter, I sit on it or give it a good hard squeeze to backflush the filter. I also use a faucet adapter to blast water through backwards at higher pressure when I get home or to some place with a faucet. Also, run a little bleach-water when you get home to prevent microbial growth in the filter (most people don't do this and would be astonished to see what the inside of their filters look like).
Likewise the guy who made the video I shared above backflushed regularly and stated as such in his video. If you compare the filters in side-by-side tests, you will get a lot better performance out of the larger Sawyer filters than the mini. If you never backflush them, they will clog up too until you do, but they are much less hassle overall. For an extra ounce or two, you get at least 10 times less hassle. Seems very worth it to me.
Here are the weights of all 3 filters, when recently-used (so wet) but shaken out as much as possible, representing actual "trail weight":
Mini: 52.8g
Squeeze: 93.7g
3-way: 109.0g
The two fittings for the squeeze (blue and grey screw in/on pieces) weigh an additional 12.3g bringing the Squeeze weight up to 106g, and then there’s the weight of quick-disconnect fittings and short pieces of tubing if you want to add that functionality that I’m not even counting, which is already built-in to the 3-way. The 3-way weighs about double what the mini does, but is such a massive difference in performance it is well worth it. 109 grams is less than 4 ounces. Until recent years, backpackers commonly carried filters that weight upwards of a pound - some still do. I really don't think that when you have a very good option that weighs less than a quarter pound, that you need to worry about shaving off half of that and ending up with a problematic system you will not want to use. The Squeeze is a good filter, and more commonly available in retail outlets. The 3-way is even better.
All use the same fundamental design but have varying amounts of porous tube surface area inside the filter. One of the biggest issues with these filters is when you have an air bubble stuck on the intake side - it can be pushed through but it is difficult - the filter allows water to pass a lot more easily than air. You can make improvements over the guy in the above video by letting air out of the tubes and then holding them pinched before attaching them to the filter, etc. but no matter what, you're going to end up with some amount of air to deal with. The larger the filter's porous surface area, the less of an issue that is, or more precisely, the faster it can be dealt with. Beyond that, there is the simple matter of how fast water can pass through the filter given the same amount of force (whether by gravity or squeezing). Also the mini's narrower housing seems to have more of an impact than the simple size difference would imply. I could speculate as to why but really won't know for sure unless one day I crack the filters open to compare the insides.