Why We Like The MSR Guardian Purifier System
Details
- Pump-action purifier for backpacking and trekking
- Self-cleaning design for easy maintenance in the field
- Effective against protozoa, bacteria, viruses, and particulate
- Water bottle adapter ensures convenient refilling
- Item #CAS008I
- Purifying Element
- Hollow Fiber
- Eliminates
- protozoa, bacteria, viruses, particulate
- Filter
- Guardian
- Pore Size
- 0.02 micron
- Cartridge Life
- 10,000+ L
- Action
- pump
- Flow
- 2.5L / min, 30/35 strokes / L
- Field Cleanable
- yes
- Includes
- water bottle adapter, cartride replacement indicator
- Dimensions
- 8 x 5in
- Claimed Weight
- 1lb 1oz
- Manufacturer Warranty
- limited 3 years
Reviews
Q&A
Overall Rating
4 based on 128 ratings
Review Summary
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Selecting an option will reload the available reviews on the pageJuly 18, 2024
Amazing product!
I bought this 2-3 years ago for use on scout backpacking trips and emergency use during hurricane season. The thought was to have zero worries with water supply no matter where I was. The troop had another MSR filter with lower filtration pumping 1L per minute. Scouts became impatient and those were quickly abandoned to use mine. Win #1! We recently took a long distance backpacking trip and most groups used micropur tablets for sterilization, but not wanting to wait used this filter instead for immediate water consumption without an altered taste. Water supplies were typically streams or in some cases cisterns from rain collection or pumps which still needed sterilization. Win #2! One camp ran out of water in their cistern with zero streams for decent water nearby. I said not a problem and we filtered out of a cattle pond full of all kinds of bugs, algae and things no one wanted to deal with. This pump had zero issues and no one got sick. Win #3! Lessons learned: most of the time, filtration just occurred over one or two days, this last trip was longer. If the nalgene was too tight, it would cause leaks between the filter and the water bottle. The same occurred if the gray ring at the bottom was too tight to the red cylinder on the filter. Loosening those connections brought everything into alignment with no leaks. A gentle tightening was all that was needed. After each trip, I do pump some clean water through the filter thinking one or 2 extra liters won't impact the life of the filter. I hang the filter to dry out the entire length of hose, and invert the filter section with fibers so it drains as well. I've had zero issues with the performance of this filter and have full confidence whenever it is used. I still carry the maintenance kit with me, but it has yet to be used.
Originally reviewed on a Cascade Designs brand site
July 12, 2024
Works...if you win the lottery on a working one.
I had to watch a youtube video of a guy having to modify his stock item to make it serviceable. Recently, a colleague of mine attempted to use his for the first time in keeping with redundancy out in the field...he bough the same as mine. The MRS Guarding leaked from various places. These were the piston rings, the lower gasket sealing the filter element. Mind you, this was snow melt, extremely clean water. Please fix this issue or offer replacement item.
Originally reviewed on a Cascade Designs brand site
June 14, 2024
Why haven’t they released a gap ring??!
This filter is great except the tolerance flaw in the design where the whole bottom leaks contaminated water all over your hand and clean water bottle because the gasket doesn’t seal when the filter is screwed in all the way. The solution I was given was “just unscrew it a bit” yea well every time you have to screw a new water bottle on, that changes the gap and leaks again. Ridiculous! Why hasn’t MSR come out with a gap-ring (or set of thin rings?) to fix this very obvious design flaw? It’s like you out half-a-decade into the design and then didn’t test it and when customers told you about the flaw you didn’t fix it and didn’t come out with an easy solution. If you fixed this issue in subsequent models I’d like a replacement. If not, I’d like your design team to sell a gap-ring to allow me to tighten it down all the way so I don’t contaminate my water… thanks.
Originally reviewed on a Cascade Designs brand site
April 2, 2024
Not a product to stake your life on
This product has a certain shelf life before the filter dries out making the purifier useless. I bought my purifier and put it away (3 years) in an emergency kit. Then I took it out to try the integrity test which it failed. In fact the filter has dried out. There is NOTHING in the manual that states how long this product can stay dry after purchase before the filter dries out. I have lost my faith in MSR as well as a great deal of money.
Originally reviewed on a Cascade Designs brand site
March 4, 2024
Reliable, use it correctly
I have used this product multiple times and have not experienced any issues. Watch videos on line to ensure you know how to use and clean it. What’s nice about this is that it can quickly filter large quantities of water and it tastes great. So if you are hiking or backpacking with a larger group you can serve many people and share the load.
November 13, 2023
Great filter until it fails
I bought the Guardian a few years ago planning for a trip that never happened, so it stayed unused and untouched in storage for about 3 years. Then I took it on a hiking trip through Lapland, where the seal failed on the first day during the filling of the second 1l bottle. I had the instructions with me and went through them as described, so this was not user error. This filter is a flawed design with much potential and reading the other reviews, MSR didn't fix the problems yet. If they ever do I might give it another try, simply because the first bottle filled wonderfully quick. I'm very disappointed with this product.
Originally reviewed on a Cascade Designs brand site
November 1, 2023
Broke since day 1
I bought it two days ago as a present for my wife's birthday to use it in her upcoming trip to Nepal. When I tested it, it start leaking. I tried to disassembled it by hand just to find out that the end nut was broken. Very disappointing. I'm wondering about those military standards...or it is just a trick to by very expensive and not reliable kit. I will ask the shop for return but I doubt I will buy again this purifier.
Originally reviewed on a Cascade Designs brand site
September 21, 2023
Too risky and poor service
I bought the Guardian for treks to faraway places. With the bottom gasket leaking and the real possibility of some moving parts breaking or getting lost I have decided that this is too risky as a sole source of clean water. Probably the GUARDIAN GRAVITY WATER PURIFIER would be a far better option (but I now don't have the money). MSR have NEVER responded to my emails. It even took me one year after ordering the Guardian to receive it. Spare parts or spare filters might be too much to hope for.
Originally reviewed on a Cascade Designs brand site
September 18, 2023
Not reliable enough
I have the Guardian Purifier (I had to wait over one year to get it). Water leaks out from the lower gasket and from the reviews for this product it seems that we will have to look out for certain plastic pins to fail as well. In light of this we will probably not take this Purifier on our backcountry trips. Here in Australia you can't even get replacement filters or parts. I wish we had waited for (never knew it was coming) for the Guardian Gravity Purifier that would it seems eliminate all of the above problems. This is also a problem for Australians because this item is not available. When you try to buy from overseas they tell you they are not allowed to send to Australia. Ever heard of Catch 22? Thank you.
Originally reviewed on a Cascade Designs brand site
September 11, 2023
Great When It Works...But You'll Want to Take a Backup
TAKE A BACKUP! We bought the Guardian wanting the best purification solution that would give us peace of mind no matter where we traveled. Put it to work for the first time on a short trip to Lake Superior, MI backcountry where it was likely overkill. I had read the reviews on this site, on REI's and on various other reputable sources and heard enough good things to give it a shot. The Guardian is terrific when it is working properly, fast flow rate and smart design that make it simple to use. But, you'll notice that many of the negative reviews point out that there are specific failure points. I am glad I paid attention to them and brought a smaller back up filter and chem treatment because on our last night in the woods the o-ring failed and water was pouring out of the bottom of the filter assembly from all sides. Needless to say, "disappointed" doesn't accurately describe my reaction. I hope MSR can make this situation right for me personally, and more importantly fix the robustness issue or at least issue guidance on how to prevent it from happening in the future.
Originally reviewed on a Cascade Designs brand site
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