The MSR MiniWorks EX Microfilter Water Filter

The MSR MiniWorks EX Microfilter Water Filter

The MSR MiniWorks EX Microfilter Water Filter

When I first began trampling the Boreal Forest and the high alpine, I would often quench my thirst by dipping my cupped hands into a creek, a river or a lake.

This primitive method worked well and it always managed to quench my thirst.

One sunny, summer afternoon while walking the banks of the Racing River in northern British Columbia, I was rudely awakened from these wild drinking habits. I had been fishing for Arctic Grayling and the fishing had been good. Less than a few dozen casts had produced two beautiful Arctic Grayling fish.

I was a happy camper. They were great fighters, and the thrill of a fish on a fishing rod, on a fast-moving river, is hard to explain but easy to remember.

I quickly cleaned my catch and headed up river towards my truck. They would make a delicious meal at the campfire, that evening.

I had been subsisting on dehydrated foods for almost a week and the thought of a real meal of fresh trout baked over an open fire, under the stars, was very appealing.

It was hot, and I was thirsty, so just as I had done hundreds of times before, I cupped my hands and dipped them into the ice-cold, raging waters of the river.

I was exhausted from a long backpacking trip into the alpine, and I was working my way back to my truck as I fished my way back home.

These northern rivers are fast-flowing and icy cold, and drinking this water is a very sobering experience. A few quick scoops of this teeth-freezing water, did the trick, and I continued on my way up the river.

As I rounded a bend I could see and hear a family of Ravens cackling away, over the decomposing carcass of an enormous northern moose. It was as if I had been struck by lightning!

I had been drinking this river water!

Crazy thoughts flashed through my head as I stopped to gaze at this decomposing pile of moose bones, slowly being leeched into the river.

The MSR MiniWorks EX Microfilter Water Filter

At that moment, on the Racing River, many years ago, I was convinced that getting a water filter might not be such a bad idea after all.

That evening sitting by the campfire and enjoying my Arctic Grayling I decided, then and there, that I would get a water filter before my next trek into the alpine.

Over the years I have made my way back to the alpine many times, and I have grown to appreciate this small and lightweight piece of equipment. It has served me well, through all the miles of up and down, in the beautiful British Columbia backcountry.

Product Description

The MSR® Miniworks™ EX microfilter water filter is lightweight and has an easy pumping action. The carbon-cored ceramic element is the MSR WaterWorks™ EX filter but without the final membrane filter.

The side-mounted lever is easier to use than bicycle-pump-style filters.

The base of the filter is threaded to screw directly onto Nalgene® wide-mouth water bottles or all MSR Dromedary™ bags, reducing spillage and the risk of cross-contamination with unfiltered water.

The over-pressure relief valve vents water back down the intake hose, so you don’t get soaked with untreated water.

Product Details

Product Dimensions: 10 x 4 x 7 inches

Product Weight: 1.01 pounds

Product Website:

Best Place To Buy: Amazon 

Amazon Prime: Try the 30-day free trial

Product Rating: 4 out of 5 stars at Amazon, over 500 customer reviews

This water filter can also be purchased at other sporting goods retailers.

The Good, The Bad and The Ugly

The Good

  • weighs only 456 grams, a little over 1 pound
  • field maintainable and cleanable
  • 85 pump strokes per liter
  • the included ceramic filter will filter 2000 liters of water
  • Foam pre-filter included.
  • filters at 1 liter per minute flow rate using AirSpring™ air bubble technology.
  • it uses a ceramic filter which has a carbon core.
  • it is effective against bacteria, particulate, and protozoa
  • it will filter to 0.2 microns or larger bacteria
  • reduces concentrations of some chemicals (including iodine and chlorine).
  • reduces odors and tastes
  • A gauge is supplied so you can determine when it’s time to replace the ceramic filter element.
  • foam pre-filter included.
  • made in the USA
  • limited lifetime warranty

The Bad and The Ugly

  • it will not filter viruses.

Who is this product for?

This recent study shows the ever-increasing need for the vigilance of our water supply.

Virtually all surface waters are contaminated with at least one of the three types of potentially disease-causing microorganisms: protozoa, bacteria, and viruses.

A 1992 study found that 97% of U.S. rivers and lakes contain one or both of the protozoan parasites Giardia and cryptosporidia.

While it is true that you can drink directly from any water source, it is critical to understand that each time you do, there is a chance of ingesting one of these bugs.

Infection symptoms can range from an upset stomach to debilitating illness and, depending on where you are, can mean anything from a simple inconvenience to a life-threatening situation.

Since these microorganisms are impossible to see with the naked eye, taking proper precautions with any water source, is always a wise idea.

Tools for maintenance

An MSR Water Filter Maintenance Kit is available at Amazon, and

the Ceramic Element can also be purchased there as well.

The Maintainance Kit and an extra Ceramic Element are not immediately necessary at the time of purchase, although I would recommend purchasing the Maintenance Kit as soon as possible.

Final Thoughts

This was my first water filter purchase and I have been using this Microfilter for many years. It is quite rugged and I have filtered water from tiny, slate based mud holes for days in the high altitude at the base of some patch of snow.

There are more expensive and perhaps better water filters on the market. This a water filter that I have been using for many years.

I change the o-rings every season and the ceramic filter about every 2 or 3 seasons. The included gauge determines this for me. I take care of my wilderness gear just as I do with all my stuff.

It has served me well over the years and I continue to use to this day. Maintain it properly and it will do the same for you.

I clean the filter every 1 to 2 liters with a green, plastic scrub pad to maintain a good flow rate.  Do not rub the filter too roughly when cleaning. You only want to open up the filter pores. A maintenance kit is always a good idea to ensure the proper functioning of this water filter.

I would be lying to you if I said that I count the number of liters of water that I filter. The ceramic filter is rated for 2,000 liters.  

I change the “O” rings every Spring, and the red “u” shaped gauge tells you when to change the filter.

The product and cartridge design have not changed over the years and this to me signifies a great basic model.

The pump works very well. It is rugged, lightweight and reliable. With proper care and maintenance, this MSR® Miniworks™ EX water filter should last you for many years.

As with all outdoor and backcountry equipment, reading the accompanying literature and instructions, combined with regular maintenance will ensure that your hard-earned money is not washed down the river.

Comments, Questions, and Suggestions

If you have any comments, questions, or suggestions about this MSR® Miniworks™ EX water filter or other means of water filtration, do not hesitate to Contact Me with your concerns.

I try to answer them all in a timely manner.


14 thoughts on “The MSR MiniWorks EX Microfilter Water Filter”

  1. I love the simplicity of your website theme. I get the impression that you are in the process of building your website. 

    I am sure visitors can look forward to reading more interesting reviews of innovative and well-designed products.You have reviewed three innovative products which are definitely handy for use in the outdoors.Their portability is defintely a plus point for outdoor lovers who don’t want to lug heavy equipment around.The Snow Peak Gigapower Stove is very convenient for boiling water in less than 5 minutes.The Lifestraw Water Filter is a boon for those who don’t want to carry water containers or mineral water while travelling as.It can filter more water than needed – 1000 litres!  But its only drawback is that it can’t be used in arid areas. It’s ability to remove most of the impurities in water will appeal to many people who are concerned about contaminated water.Your last product the Black Diamond Storm Headlamp is another innovative and durable product for the outdoors to provide light at very low cost.

    • Thanks, Rubicon, for reading all of those posts.

      Yes, I am redesigning my website to make it more simple and user-friendly.

      If you look at the bottom left you will find a link to dozens and dozens of reviews and blog posts to keep you reading for hours and days. Go back and look at the bottom left “older posts”.

      Thanks, for the comments, and do drop by again.

      Your presence is appreciated.


  2. Great post and good info.

    This looks like a great one when you go outdoors and you need clean water, yes I saw the con that it doesn’t filter viruses. 

    But I will show this to a friend that goes outdoor a lot of times, and the is looking for one of this. 

    One question, there are better ones out there right? And how do you do this with price/quality? 

    Thanks for sharing it with us! 

    • Good Day, Emmanuel.

      There are more expensive models of water filters on the market. 

      The MSR Guardian is 4 times more expensive, and the Katadyn line is also at 4 times the cost of the MSR Miniworks EX. 

      More expensive is often better than less. 

      Lamborghinis and Maseratis are better than compact cars, but unfortunately, most of us drive the lower end models and they serve us well.

      Most of the time, you get what you pay for, but I use this model, and it has served me well over the years.


  3. This looks like a very cool product. I can definitely see its beneficial use while outdoors, as having a way to attain water is always a good thing. This definitely seems like a product that I would want if I were to do some adventuring outdoors! What is your favourite part of this products many features and benefits? Thanks for the great review/overview!

    • Hi, Kohl.

      This product has few moving parts and is easily maintained in the field. 

      Easy to change o-rings and filter. Included gauge for filter life. 

      All of this for a very reasonable price. It has also built itself a solid reputation as a dependable performer. 

      There are more expensive models of water filters, on the market, for the “better heeled”, but this product has always performed well for me.


  4. I have always been wary of drinking directly from streams, rivers and lakes precisely because the chances of contamination are so high. I have a LifeStraw personal water filter that can filter up to 264 gallons and removes 99.9% of bacteria and protozoas.  It’s smaller in size than the MSR. Have you tried it? 

    • Yes, I have Annette, 

      and the LifeStraw filter is always in my daypack when I am out hiking or camping. 

      I bring the MSR Microfilter along on longer trips or if finding water is a major issue. 

      If you scroll down further, you will see that I have a review of the LifeStraw. I use it often and I love it. 

      Thanks for reading my post and I look forward to hearing from you again.


  5. Hello Paul,

    I never knew there was such a portable water filter available in the market. My grandfather has a farm and clean portable water is not available in the environment. This would be a really useful product for his use. 

    How long does it take for water put in the filter to become fit for consumption.

    • Good Day, Louis, and thanks for reading my review. 

      This product takes about 2 minutes to filter 1-litre of water. It is primarily used for camping and hiking purposes, and the water that it filters can be consumed right away.

      Because of its size, its application is aimed at the outdoor recreation industry, for water filtration periods of days and weeks, as opposed to weeks, months, and years, as in the case of daily life on the farm.

      It can still be used for your uncle’s purpose. Water is only second in importance, to the air we breathe. Having said that, life on the farm would be an excellent test for this product.

      I would be interested to hear of your results, should you decide to bring one to your uncle’s farm.

      The ceramic filter can filter 2000 litres before needing replacement and needs to be field-cleaned often, depending on the nature of the water being filtered.

      I hope this answers your concerns, and if you have any others, feel free to return here for more answers.


  6. Great review. My father owns a farm far from the city and there is no municipal water. All the water is either from rain harvesting or boreholes. We do have filter systems in place but a small portable filter like this one will definitely be a handy addition.
    The borehole water is mineral rich that can be overwhelming for a sensitive tummy. Would this filter be able to help make it more drinkable?

    • Good Day, Jean.

      Thanks for stopping by. This filter does remove some minerals and bacteria from your drinking water. It will certainly improve your drinking water. It is, however, impossible for me to determine what is in your water supply from here.

      I have used this filter for many years, drinking water from rivers, lakes, and streams, in the wilderness. Water that has been collected in metal, wooden, or plastic containers and is standing for long periods of time is another issue.

      I would drink the rainwater collected from a clean container that has not stood for too long.

      In your “borehole water” case, I would bring a sample of this water to a Reputable Laboratory and have it professionally tested. This is the best way to find out what is in your water. It is a very small price to pay for your safety and peace of mind.

      I hope that this helps a bit and I would love to hear from you again on this issue. I would be very pleased to hear that you had the water tested in a lab. Do yourself the favor.

      All the surface waters that I have drunk from over the years have never caused any issues for me. Hope to hear from you soon.


  7. Yes, Thomas. 

    The MSR MiniWorks EX Microfilter is an excellent water filter for all your outdoor activities, whether you are camping, fishing, or hiking. 

    It’s tough and reliable. MSR produces many pieces of outdoor equipment. Simple to use and easy to clean, it has become a necessity in today’s world of questionable drinking water sources. 

    A reliable and inexpensive tool that all outdoor enthusiasts should own. 


  8. I had no Idea you could get small water filters like this for out door use,

    you learn something new every day this is an awesome review and I will defo consider buying out the next time we go camping.

    I like how easy and simple it is to get clean drink able water and how easy it is to clean.


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