Sawyer Mini Water Filter Review

Full In-Depth Review

The Sawyer Mini water filter, according to Amazon, is currently the second most popular water filter. It’s very popular among long-distance hikers, and wilderness backpackers because of it’s price, versatility, and size.

I’ve owned the Sawyer Mini for about a year now, and it’s my go-to water filter whenever I’m hiking. Essentially, it allows me to never carry more than one or two liters of water, regardless of how long my trip will be.

Sawyer Mini Water Filtering Capabilities

The Sawyer Mini is a hollow-fiber membrane, 0.1-micron water filter. According to their specifications, it filters 99.99999% of all the harmful bacteria and other particles larger than 0.1 microns. Though, it isn’t able to filter viruses, heavy metals, pesticides, and chemicals.

What this means in real life, is that whenever you’re hiking, you should look for a natural source of water that hasn’t been contaminated with chemicals or waste. For instance, safe sources could be a puddle, a river, a lake, or something along those lines. Basically, anything that isn’t near a factory or a large city. From my own experience, it’s easy to find sources like that while you’re hiking.

In terms of taste and color, the Sawyer mini removes all taste from green matter, bacteria, and dirt. If the water source is heavy in metals or minerals, it will still look a bit darker than usual after filtering, and also taste a bit different, but the water is still safe to drink.

The Sawyer Mini can filter up to 100 000 gallons / 370 000 liters of water before it needs to be replaced.

What’s Included in the Sawyer Mini Water Filter Kit

The Sawyer mini kit comes with the water filter itself, a syringe for backflushing the filter, a straw attachment for the filter, and a 16-ounce / 500-milliliter pouch.

In addition to the original kit, I purchased a set of three 32-ounce / 1-liter Sawyer pouches. That’s because the original 500-milliliter pouch was too small to be used efficiently. Whenever I’m hiking, I usually carry two 32-ounce / 1-liter sawyer pouches for contaminated water, and another 1-liter water bottle for clean water, so three liters of water in total.

If I wouldn’t have purchased the three additional, larger pouches, I’d need to carry more bottles, and every time I’d get to a water source, I’d have to collect water multiple times because the original pouch was so small. Having multiple larger pouches makes everything much easier.

For this system, I’d recommend getting additional pouches. Though, you don’t need to use the original Sawyer pouches. The Sawyer Mini can be used with any bottle or pouch that has a standard 28-millimeter thread. I found the Sawyer pouches to be a pretty good deal because you get three one-liter pouches for about 15 dollars, so I can keep one pouch as a reserve in case the other ones burst.

How to Use the Sawyer Mini Water Filter

The Sawyer Mini has two ends on it – one for contaminated water, and the second one for clean water. You can quickly distinguish between both by looking at the arrow in the middle that points to the water flow direction.

First, you need to select a water source. I usually prefer to use cleaner water sources, such as springs or rivers, but you can also use a puddle, a lake, or something similar.

The next step is to collect some water. You do that by filling the water pouches with contaminated water. I’ve found that it’s much easier to fill these pouches in fast-flowing water, but you can also fill them up in still water sources. Another tip is to use your mouth to blow the pouch up before attempting to fill it up. Just make sure to clean the cap first if the water source is really contaminated because you don’t want bacteria to get in your mouth.

After you’ve filled the pouches with water, the next step is to start filtering the water. You do that by screwing on the water filter to the water pouch, turning it upside down, and gently squeezing the water filter.

That’s basically it, but there are a few other ways on how you could use it.

The first one is to drink directly from the water filter when it’s screwed on the water pouch. I usually do that whenever I’m near a water source, for drinking as much water as I can before leaving.

Another way (and the easiest) is to skip the pouch entirely and use the straw attachment. To do that, you need to attach the straw to the end where the dirty water goes in, put the clean end in your mouth, and drink directly from the water source.

Another way is to use gravity feed systems. You can attach one end of a hose to the dirty end, and the other to a large water container on top. Personally, I haven’t tried these systems, because they take up more space, and I like to keep it on the lighter side whenever I’m hiking.

Testing the Sawyer Mini in a Water Source Rich in Sediments

I’ve always used the Sawyer Mini in somewhat clear water sources, such as creeks, springs, or lakes. For this review, I decided to test it in a really dirty and contaminated water source, which was high in sediments and had a lot of algae growing in it. Basically, it was a ditch in the middle of a forest, so while it was pretty dirty, I was sure there weren’t any chemicals in it.

When I filtered the water, I noticed that the Sawyer Mini wasn’t able to remove the yellow color from the water. This was a swampy area, so I guess the water was high in minerals and tannins, which shouldn’t be harmful to drink. One thing that I noticed though, was that the filtered water was much clearer.

Aside from the yellow tint, the filtered water didn’t have any taste or smell. It was a particularly hot day, so it was actually pretty refreshing, even though it was filtered from a dirty ditch.

Backflushing and Maintenance

If you’re new to water filters, I’ll quickly explain what backflushing is and why you need to do that. Essentially, whenever you’re filtering water, all the dirt gets trapped inside the filter. After a while of using the filter, you’ll notice that the water starts flowing through the filter slower. That happens because it’s clogged up, and you need to backwash it.

If you’re filtering clean water, then I’d say you need to backflush the filter after every 10 liters. But if you’re filtering dirty water sources with much dirt and large particles, you’ll need to backflush it more often. Personally, I backflush it after every use to keep the flow rate as fast as it can be.

To backflush the water filter, you need to fill up the syringe with clean water, press it tightly against the clean filter end, and then flush the filter with as much force as you can. You need to repeat that for about three to five times.

After you’re done, you need to get most of the water out from the filter. You do it by shaking the filter with as much force as you can until there’s no more water coming out.

Testing the Sawyer Mini Water Flowrate

A lot of people have said that they’re able to filter one liter of water with the Sawyer Mini in about 90 seconds. For me, the best flowrate that I could achieve was one liter of water in two minutes (120 seconds).

To achieve a good flow rate, simple backflushing isn’t enough. After about six months of using the filter, I noticed that the flowrate was becoming pretty bad, even with backflushing after every use. I measured that, at that point, the flowrate was about one liter of water in five minutes.

Sawyer recommends cleaning the filter with hot water and vinegar every once in a while, to restore a good flow rate. So I went ahead and boiled up some water, added a little bit of vinegar (1 : 5,) and left it in there for one hour. After that, I backflushed the filter with the hot water and vinegar mixture and repeated the whole process one more time. My flowrate improved from 5 minutes to 2 minutes per liter of water. I guess there was some mineral buildup inside the filter that regular backflushing just wasn’t able to remove.

Another thing that you should remember, is that the flowrate isn’t as good right from the start. The flowrate gets better once the filter is wet. Sawyer has said that the best flowrate is achieved only once you’ve already filtered about one liter of water. So my advice would be to stay patient, and wait for the flowrate to improve, instead of squeezing the pouch harder. Also, for better flowrate, try to use the filter in cleaner water sources and try not to stir up the water when you’re filling up the pouches.

About the Sawyer Water Pouches

I actually managed to burst the original 500-milliliter pouch that came with the kit after about five uses. I was just filtering some water, and suddenly the seam near the top cap burst open and the pouch was done. I later found online, that this is pretty common with Sawyer pouches. I also learned that you shouldn’t put that much pressure on the pouch.

Since then, I haven’t burst any more pouches. You should squeeze them until you get a good flowrate, and then stop because more pressure won’t improve the flowrate. Personally, I’ve found that it’s very easy to filter water when the pouch is folded once in the middle. When you’ve filtered most of the water from the pouch, and it’s getting harder to squeeze, instead of folding it more times, unscrew the filter, blow some air in the pouch, and screw the filter back on.

Using the Sawyer Mini With Smart Water Bottles

A lot of hikers use Glaceau smart water bottles with the Sawyer Mini. I don’t live in the U.S., and we don’t have them here, but I found a very similar bottle in a local store.

People use them because they’re made from a pretty thick and durable plastic and the cap thread is in the right size to screw on the water filter. Also, if you get one with a sports cap, then the clean end of the water filter will fit inside the hole in the middle of the cap, which makes it easier to filter the water because the clean water bottle isn’t moving around.

If you don’t like the Sawyer water pouches, you could just bring two or three smart water bottles, and get a sports cap with a hole in the middle for your clean water bottle, and a regular cap for your dirty water bottles.

Using the Sawyer Mini in Freezing Weather (Winter)

The Sawyer Mini shouldn’t be used in freezing weather. On their website, they say that the Sawyer Mini needs to be replaced if frozen. So if you’ll be using it in winter, you should always keep it in your pocket, so your body temperature keeps from freezing. When you’re sleeping, just throw it in your sleeping bag and that should be good enough.

Final Verdict

Let’s start with the pros. First of all, it’s very inexpensive. I purchased the full kit for about 20 dollars, and I paid an additional 15 bucks for the three larger, 32-ounce / 1-liter water pouches. Another one is that the whole system is very lightweight and very tiny. I also like the versatility of the Sawyer mini. You can use it as a lifestraw, drink straight from the bottle or use a gravity feed system, you can use it with regular water bottles, or you can use it in the traditional way with the Sawyer pouches. It’s hard to find other water filters that are this versatile.

And now let’s get into the cons. First, I don’t like that it needs to be backflushed so often. Second, I think that the flowrate could be improved. I know that the Sawyer Squeeze has a better flow rate and that many filters from other brands have better flowrates. And lastly, the pouches could be more durable. They’ll last if you’ll be using them gently, but if you aren’t patient, it’s very easy to burst them.

In general, I think that this is a very good and very versatile water filter, but there are a few annoying parts about it. If you don’t own a water filter yet, then the Sawyer Mini is a superb choice.