Review of the MSR MiniWorks EX Microfilter Water Filter
As of this writing, there are 501 customer comments and 59 answered questions for the MSR MiniWorks EX Microfilter Water Filter. I've read the customer feedback and then condensed the results into this review. I hope that this helps you when shopping for a portable water filter.
Best Features
Item Specifics
The MSR MiniWorks EX Microfilter Water Filter is great for hiking, backpacking, camping, travel, survival, and emergency preparedness. It uses a replaceable carbon and ceramic filter to remove bacteria, protozoa, organic compounds, and particulate, delivering clean, taste and odor-free water. It pumps at a rate of one liter per minute. This product can be used with a variety of wide mouth water bottle and hydration bladders. The MSR MiniWorks EX Microfilter Water Filter meets NSF protocol P231 for removal of bacteria (99.9999%) and protozoa (99.9%). One replaceable filter cartridge treats up to 2,000 liters of water. This portable water filter measures 7.5 x 2.75 inches and weighs 1 pound. A storage bag is included. This product is made in the USA. It also has a manufacturer’s limited lifetime warranty.
Makes Water Taste Clean
What customers liked the most about this product is that it makes water almost tasteless. Water that was the color of tea did not have a taste and looked fresh. Here is what one customer said, "The water came out crystal-clear and almost tasteless. It didn't taste like Dasani bottled water, but it definitely didn't taste like tea-colored lake water either. Pretty much neutral. More importantly, it tasted CLEAN and nobody got sick."
Clogs Easily
According to customers, this portable water filter can clog easily. When it does this, you must clean it or it may break. Here is what one customer said about it clogging, "I bought this for a 6 week hike in the mountains. The water was quite clean to begin with. However, the unit clogs often and you have to scrub the ceramic unit with the supplied green pad. It will start working again, but slows down again after a few liters of water. It is physically demanding to use. Not hard, but if you're supplying water to two people on a backpacking trip your arms are going to get a workout along with your legs...If it's too hard to pump the water then you MUST clean it or you will break it."
Small and Compact
Customers liked that this product is small and compact. It is going to be larger than straw filters, but is also much smaller than the Katadyn Vario Dual Technology MicroFilter. Here is what one customer commented, "It is lightweight (I used to have a Katadyn, which is built and weighs like a rock), so it's not going to add too much to your pack. It's heavier than chemicals or some of the UV systems, but it's not bad. It comes in a nice little mesh bag, so you can stuff it into a corner of your pack."
Slow
According to customers, this is a slow pumping water filter. It clogs easily, and even when it doesn't clog it can be slow to pump. One customer had this to say, "This is the slowest filter I have ever used. The packaging states that it will pump around 1 liter per minute. I was pumping for over 3 minutes per liter. I followed all the instructions and it was horrible. I returned the next day after my hike."
Slower with Dirty Water, but Still Filters It Well
A lot of the customers who reviewed this product were using it on clear streams. But a few customers decided to test this product on questionable water that was dirty. The result was that the water came out clear, but it was harder to get the water to come out. Because it is filtering out more bacteria and other stuff, it will take slightly longer to pump. But it works great according to customers, and even questionable water can be made odorless and tasteless. This customer shared his experience, "Unlike some others people, we actually tested this in a very questionable, dirty, dark water pond, not some fancy clear stream. That being said, pump operation was slightly more difficult (it has a lot more to filter) and thus flow rate was slightly reduced. Water came out clean and odor free. First couple liters had that new filter taste, but aside from that, taste was of clean tap water. My self and several others drank at least one liter and I have drank over a gallon I took home in my water carrier. No medical issues what so ever."
MSR vs Katadyn
There were mixed reviews on if this portable water filter is better than the Katadyn Vario Dual Technology MicroFilter. The MSR MiniWorks EX Microfilter Water Filter is light weight, but some customers found that the Katadyn was stronger and more heavy duty. Here is what one customer thought when comparing this water filter to the Katadyn,
"The MSR is of similar design to some other filters such as the Katadyn Vario Dual Technology MicroFilter. They will filter down to the same size (2 microns) which will eliminate pretty much anything but a virus. I believe both of these will function similarly and at the same rate. I've not used a Katadyn but I've seen evidence that they are a bit more complex and possibly a little less rugged. That can be good or bad depending on your goal. There is apparently a couple of settings with the Katadyn that offer a high rate of flow or a long filter life. From the research I've done I think the Katadyn is a bit "cantankerous" to use. From my use of the MSR, it is not. It is very simple and pretty rugged. The only weak points I can see are where the inlet hose attaches to the pump head and the hinge of the handle. The inlet point will be a problem on the Katadyn as well, and the handle probably will. But I think on both filters it will only be an issue if you torque the handle in an "unnatural" directon. For simply pumping it is very well made."
Fits All Kinds of Bottles
Customers mentioned that this water filter fits on a lot of water bottles. Here is what one customer said, "Great little filter system. Easy to use and filled a 100 oz camelbak reservoir in a few minutes...Several people have mentioned that the filter fits Nalgene bottles, however, several people in our group had generic large mouth water bottles and the filter fit all of them...Definitely worth buying."
Great Price for What You Get
The price is higher than straw filters, but compared to other pumps this is at a great price. Here is what one customer commented, "Great product. Was a little bigger than it looks in the picture, but easy to clean to and fill up your water bottle. For the price I would highly recommend. When I got it it was about $60."
Lasts a Long Time
The description says that this water filter will filter up to 2,000 liters of water. After that, you'll need to replace the filter. Some of the customers who have used this product said it has worked for many years. Here is what one customer shared about the filter which he has had for 10 years, "Best backpacking, survival, expedition filter you can get at a very reasonable price. I've had mine for about 10 years now. At least a few hundred uses and I had to buy a new element for the first time ever. Unit has been dropped, sat on and heavily abused. Never had one problem."

Pros
Cons
MSR MiniWorks EX Microfilter Water Filter Conclusion
The MSR MiniWorks EX Microfilter Water Filter uses a replaceable carbon and ceramic filter to remove baceteria, protozoa, organic compounds and particulate. The rate at which it pumps is one liter per minute. This filter can be used with a variety of wide mouth water bottles and hydration bladders. The MSR MiniWorks EX Microfilter Water Filter measurers 7.5 x 2.75 inches and weighs 1 pound. Included with the filter is a storage bag. This is a USA made filter that comes with a manufacturer's limited lifetime warranty. According to customers it is slow to filter and it clogs easily but it is priced low for what you get and it filters water well.
Common Questions
Here are some top questions that I found for people considering buying the MSR MiniWorks EX Microfilter Water Filter.
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