Sawyer Mini Water Filter

Review: February 2, 2019, July 17, 2021
I’ve used this water filter for 4 years and had another one that I had used for a couple of years until it froze on a trip in Yosemite. I had left my filter outside during the night. Due to the microfiber construction there is no way to test the filter for internal integrity when it freezes. Water expands when it freezes and the microfiber tubes can rupture inside the filter.

I’ve modified my water filter by taking a bottle cap that fits on the Platypus water system I use. I’ve taken the plastic cap from a 20 ounce plastic bottle, drilled a hole in it, and super-glued it to my Sawyer mini-filter. This allows me to easily fill my Platypus bladder and backflush my filter when I get home.

Use a Smart Water bottle and not the bag that comes with the Sawyer Mini Filter. The water bottle is much easier to fill. The trick to using the water bottle is that after you have squeezed about 1/8 of the water through the filter, unscrew the bottle just enough from the filter and squeeze the sides of the bottle so air is sucked in and the bottle mostly regains its shape. Then screw the bottle snug again and squeeze through more water. When you get good at this, only a drop or two of water escape each time you unscrew the bottle.

Do’s and Don’ts

Do try to get the extra water out of the filter. I rinse off the filter and first blow through the input then swing it downward several times to have the centrifugal force drive out most of the water.

Do backflush it when you get home. I like to do this after every trip. I flush about 8 ounces of water back through the filter.

Do try to keep it out of direct sun. A high internal heat buildup could damage the inside.

Do leave the cap off it for about a week when stored at home. That allows the filter to thoroughly dry between uses.

Don’t let the filter freeze. Bring it into your tent at night and if it is really cold, have a plastic zip seal bag to sleep with it.

Don’t lose it between trips. The filter isn’t very large and is easy to misplace unless you always keep it in the same place at home.

Don’t (in my opinion) use it as an in-line water filter in your hydration system. I tried that and got severely chapped lips from not drinking enough water. It seems logical that sediments in the water will slowly restrict flow over time. I’ve talked to some people who have used this inline successfully on trips.

Additional Photos