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MSR MIOX Water Purifier
$139.95
Item qualifies for annual
REI Member Refund (typically 10%)
The MSR MIOX® purifier makes water microbiologically safe using salt and an electrical current. Click on the Video tab to watch how it works.
- Proprietary patented technology creates a small batch of an oxidant solution which is mixed with your water to destroy microorganisms
- MSR MIOX uses a chemical reaction called electrolysis to create a powerful disinfectant that will destroy biological contaminants in your water
- More effective against microorganisms than chlorine or iodine
- Destroys viruses and bacteria in 15 minutes, giardia in 30 minutes and cryptosporidia in 4 hours
- Features a safety indicator so you can be sure your treated water is safe to drink
- Comes with 1 oz. of salt to treat 200+ liters of water; 2 lithium CR123 batteries; 50 test strips; instruction book; reference card; storage bag
- MIOX is compact, rugged and submersible
- Purifies water without iodine; no health risk or unpleasant iodine taste
Made in USA.
Item 709012
MSR MIOX Water Purifier Specs
Specification | Description |
| Weight | (pen only) 3.5 ounces |
| Dimensions | (pen only) 7 x 1.25 x 1 inches |
| Material | Salt |
| Removes/Destroys | Protozoa, bacteria and viruses |
| Output | NA |
| Pump force | NA |
| Pump strokes per liter | NA |
| Field cleanable | Yes |
MSR MIOX Water Purifier Customer Reviews
REVIEW SNAPSHOT®
by PowerReviewsPros
- Lightweight (30)
- Easy to clean (22)
- Maintenance (21)
- Good filtration (6)
- Easy to pump (3)
Cons
- Filtered water doesn't taste good (5)
- Poor filtration (5)
Best Uses
- Backpacking (29)
- Hiking (22)
- Day trip (14)
- Car camping (6)
- Reviewer Profile:
- Avid adventurer (22), Casual/ recreational (8)
Reviewed by 32 customers
Sort by
Pros
- Easy to clean
- Good filtration
- Lightweight
- Low maintenance
Cons
Best Uses
- Backpacking
Comments about MSR MIOX Water Purifier:
Here's the deal, this thing will have problems if the water you are using is cold. The reason is simple, the rock salt that is used is in this thing has to go in solution. If it is cold it doesn't dissolve enough and it just gives you a red light saying insufficient salt. If you can warm the water up you are ok otherwise it isn't going to work.
The plastic tab that goes from top to bottom is too short on mine making it way too easy to cross thread the top cover is the only other gripe.
When it works great, but if the water is below about 45-50 degrees you are going to need to shake this thing a lot or it is going to do nothing.
- Gift:
- No
Pros
- Easy to clean
- Lightweight
- Low maintenance
Cons
- Expensive
- Not a filter
Best Uses
- Backpacking
- Day trip
- Hiking
- Military
Comments about MSR MIOX Water Purifier:
as an avid outdoor guy who makes his living in the military traveling around the world to places that never, ever have reliable water sources, the MIOX purifier is a must have item. i've gotten extremely sick from bad water sources in the past. if you've ever experienced such problem, you know it's not something you want to play with. i agree with others that i don't worry about the strips. i double dose everything. my MIOX uses batteries and salt rather conservatively. if you're in the military and are always having to make choices on what you're bringing along on any mission, this guy saves weight and space without a doubt. it fits in a camelbak pocket easily. it also works great for an escape and evasion kit. this is definitely must have gear. while it is expensive, its cost is worth the peace of mind of not getting sick. also keep in mind that it's not a filter. if your water source has "crunchies" in it, you'll be drinking those but they're not going to make you sick. but also keep in mind that filters do not rid your water of viruses. only a purifier can do that. the MIOX rids your water of 100% living organisms. go buy one now!
- Gift:
- No
Pros
- Lightweight
Cons
- Requires Batteries
Best Uses
- Backpacking
Comments about MSR MIOX Water Purifier:
I was initially very excited about this product; it is compact, lightweight and when used properly effective against even cryptosporidium. However, after spending several days attempting to purify water with the Miox, I would not recommend this product due to multiple shortcomings. In order to prepare the brine/oxidant mixture that will purify your water, you must have batteries, crystals and pH strips to check that you have properly completed the process. I found the crystals to diminish far more quickly than one would expect from the manufacturer's information. Furthermore, as our trip progressed, the strength of the oxidant became weaker and weaker, requiring more volume to meet the pH indicator test for potability. I would assume that this was in part due to the batteries weakening and the crystals shrinking. I eventually became so fed up that I used iodine for the last day and a half of the trip. I found function of the Miox dependent on too many factors, making it inconsistent and more hassle than it is worth.
Pros
- Easy to clean
- Lightweight
- Low maintenance
Cons
Best Uses
- Backpacking
- Hiking
Comments about MSR MIOX Water Purifier:
I've never owned a filter because they are heavy and a hassle to carry and use. Most chemical treatments have their disadvantages, too. I've settled on the Miox as the best treatment method for me. It's easy to use (I never bother with the strips) and it's great for treating large volumes of water for big groups. Since I often lead groups of 12 on week-long volunteer trail work trips, the Miox is really the only reasonable water treatment method. It does leave a slight chlorine aftertaste in the water, but this dissipates over time and in any case has never been strong enough to bother me. A fresh set of batteries generally lasts most if not all of a hiking season, which for me is about 4-6 weeks in the backcountry, treating water for groups of up to 12 people. I'm not sure how many gallons that is, but it's quite a few. At least 50. Still, it's a good idea to carry a spare set of batteries.
Pros
- Easy to clean
- Lightweight
- No Maintenance
- Water Fast
Cons
Best Uses
- Backpacking
- Car Camping
- Day trip
- Hiking
- Travel
Comments about MSR MIOX Water Purifier:
I did all the research and went back and forth as to what would serve me best in a variety of situations. I bought this over a year ago and couldn't be more pleased with it. I wanted something that didn't take much room, was light, and would work for backpacking and travel to places where the water is questionable to say the least. I decided on the MIOX because it was smaller and lighter than a filter system, with no chance of getting clogged or having to maintain it. I also decided against the UV option because it will not work if the water is dirty and the light can't penetrate (now I don't like to drink murky water, but if I had to the MIOX would actually ensure it was virus and microbe free). So long story short, it has worked wonderfully. You do need to hit the bottom of it down on to your hand to get the salt water past the screen, but it is not a real detraction. It works much faster than sitting and filtering water forever, and it leaves little to no taste (I only detect a faint taste if I over treat the water, but if I let it sit overnight, i.e. in a camelbak, there is no taste in the morning). All this said, it isn't for everyone. Nevertheless, it a very good solution for many.
Pros
- Easy to clean
- Easy to pump
- Lightweight
- Low maintenance
Cons
- Filtered water doesn't taste good
- Poor filtration
Best Uses
- Backpacking
- Day trip
- Hiking
Comments about MSR MIOX Water Purifier:
I've used this on about 10 week long backpacking trips and some weekend trips. Sometimes it works great - when it is warm. When it is cold it takes 2-5 tries to get enough oxidant and you end up using a lot of test strips. Also, it obviously isn't good for dirty/murky/smelly water. And like any chemical treatment you must wait 30 minutes before you can drink. The water tastes like chlorine.
- Gift:
- No
Pros
- Easy to clean
- Lightweight
- Low maintenance
Cons
Best Uses
- Backpacking
- Hiking
Comments about MSR MIOX Water Purifier:
The Miox purifier has consistently lived up to its promise. It's simple and reliable. We use it to purify large quantities of water and it works superbly. I agree with others that it's often easier to just double to dose and forget about the test strips. Battery life has been great. I mainly use it with a crew of 12 scouts on multi-day backpacking trips, and we've found it to work really well.
Pros
- Easy to clean
- Easy to pump
- Fast
- Lightweight
- Low maintenance
Cons
- Batteries
Best Uses
- Backpacking
- Hiking
Comments about MSR MIOX Water Purifier:
I bought this for a long distance hike on the AT. I must say the test strips are difficult to use, but are not strictly required. The instruction pamphlet lists an "overkill option" of overdosing the water by 8X This means using the 4L option twice for each liter. I would treat water for the next day before turning in for the night, and the chlorine taste would be gone in the morning.
The unit did suck down batteries far in excess of the manufactures guidelines using the overkill option, and in cold weather it takes even more juice out of the batteries. I was able to find CR123 rechargeable batteries, and they lasted the 10 days or so between resupplies. This would be a great way to do multi-week hikes.
Added bonuses to using the unit:
It is a good hand sanitizer, especially if you splash the water on your hands when rinsing the water bottle threads. It also serves replacement for washing that water bottle. We've all had the Nalgeene funk from Kool-aid etc in our bottles, and this does a good job at combating that. I use this to clean my pump filter when I take that instead (usually in the winter - who wants wet hands in the cold?).
In short, I really recommend this product.
Pros
- Lightweight
Cons
- Half hour wait time
Best Uses
- Backpacking
- Hiking
Comments about MSR MIOX Water Purifier:
I have had the MIOX for a year and a half now, and am satisfied with its performance. I think it is the best option for chemically treating water. Although treated water carries a faint chlorine smell, there is almost no foul taste (a welcome change from iodine). Weight and relative ease of use are the MIOX's chief advantages. Disadvantages (aside from the price) are the half hour treatment time and imperfect mixing with salt crystals that sometimes requires multiple attempts to create the right cocktail. If you also use the test strips included in the package (I don't as I am rarely all that worried about the water I drink) purifying water becomes somewhat time consuming, if not as aggravating as using a pump. Still, nothing is perfect, and the MIOX is a solid choice.
Pros
- Easy to clean
- Good filtration
- Lightweight
Cons
Best Uses
- Backpacking
- Day trip
- Hiking
Comments about MSR MIOX Water Purifier:
The Miox pen is, in my opinion, the single best chemical water treatment option available. It’s lightweight, easy to use, fast, and, properly used, has no danger of ruining the stuff in your bag around it. While it initially imparts a slight taste to water (much more so to treated tap water than untreated water, believe it or not), it is so mild as to be undetectable much of the time, and dissipates after letting the water sit for a short while. The mixed oxidant solution produced by the MIOX works great for purifying water, and on the strongest setting, can do wonders for stinky socks when doing laundry in the sink at youth hostels. Regarding the little "pH" strips (they're not, they actually test Chlorine content), I occasionally use them, but for the most part just use double the minimum dose and have never been sick. Most water I have tested with the strips is not adequately treated with the normal dose, and all of it has been good with a double dose. Overall, a great product!
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