Reader Reviews

Rating: 5 / 5

Normally I use a Steripen Aventurer for water treatment and carry MSR tablets for a backup. But I use a filter when going to an area with unknown water quality or into an area I know requires a filter due to particulates.

Introduced in spring of 2008, I purchased the MSR Hyperflow filter as soon as I could find one at a discount at REI. It retails for $100; I used a 20% discount coupon. I’ve used it enough now to begin a review process here at BPL.

I jettisoned the wide mouth bottle lid since I use a platypus hydration system. And I don’t carry the supplied nylon and mesh bag that comes with the filter.

Advertized weight is 7.4oz. Measured on my scale it is 8.3oz with filter, one hose, and the pre-filter. This is over 4oz lighter than the Katadyn Hiker I sometimes use.

Wrapping the input hose around the filter and securing it with the velcro on the pre-filter makes a comparatively small, neat, and easy to manage package.

In use I find it takes approximately 10-11 strokes to acquire 0.5L of filtered water which matches the advertized flow rate of 1L per 20 strokes. This flow rate is acceptable for me. The pumping effort I would describe as moderate or average when compared to other filters I have used.

I was skeptical about the odd shaped pre-filter but have so far found it useful. It works surprisingly well in calm and slow moving water but must be weighted down with rock in fast moving water; otherwise it floats on the surface and causes the filter in “inhale” air, which results in inefficient pumping.

Maintenance is fairly easy. One can back flush the filter by disassembling the pump and reversing the 2 “rubber” valves in the pump. You must remember which way the valves face when you disassemble the pump so you get them back in the correct orientation. The nylon storage bag does have attached instructions which will be useful if you elect to carry it.

Unfortunately for me the output nipple on the pump is slightly larger that the Platypus hoses I prefer to use so I cannot use my preferred hoses. The MSR hose, especially when new, attracts dirt and debris which I find to be a nuisance. The good news for Platy users is the output assembly on the pump is sized to form a tight seal when inserted into the narrow mouth Platy bottle. This is an acceptable mechanism. Of course one can attach an MSR hose to the output nipple as well. I can work the Platy bite valve onto the MSR hose. (Note: Unfortunately I found that MSR Sweetwater hoses are a different ID size than the hoses supplied with the Hyperflow pump and won’t fit the input/output nipples)

I like the transparent pump body on this pump much better than the opaque bodies of Katadyn and other filters. One can see the cylinder being filled and check to see if too much air is entering the pump.

To date I am very satisfied with this pump. I'm giving it a 5 based on my experience with other pump style filters. In the overall scheme of water treatment solutions I certainly would not rate it that high.

Edited by ThinAir on 06/12/2008 09:33:07 MDT.

Rating: 1 / 5

My experience with this filter was frustrating.

I purchased one of these at my local outdoor store. After studying the directions and test cleaning at home it went with me on a 6 day trip into the wilderness. After this one trip I returned it.

This unit is very fussy to clean. They recommend cleaning after every 8 liters pumped or about once a day. You can't tell if it's dirty or clean, because you can't see the element. It breaks if dropped or frozen, but it's very hard to tell if it's broken. There's a bubble test and a compression test to check for breakage. But no apparent signs.

I dropped by my local store today and my salesman had talked with his MSR rep. They told him that many people are getting an airlock when cleaning the filter. This can happen if you pump it at the wrong time while reassembling the fussy little pieces to create a back wash. And here's the really bad thing. Once you have an airlock the element is ruined and must be replaced! This is the first I'd heard of this. The rep said MSR was replacing the elements of airlocked filters for free. hmmmm.

When I bought mine, I attempted to get a replacement element to carry in case I broke the first one and I could not find replacement elements anywhere locally or on the net.

I would not recommend this filter for field use. Too fussy to clean. Can't tell if it's broken. Cleaning can create an irreversible airlock. One other thing, you must use filtered water to clean it.

Rating: 5 / 5

Hello All -
I’m the Brand Manager here at MSR. I’ve been tracking these posts because it is important to us to hear your unsolicited, third-party user experience. However, I wanted to post an important correction about the air-lock issue. Although it is true that an air-lock can occur while cleaning the filter, an air-lock absolutely DOES NOT damage the element and it DOES NOT need to be replaced. To relieve (i.e. release) the air-lock, just reverse the check valves so they are configured again for forward flow, pump a few pumps of water through then begin again with the backflushing directions. Admittedly, the HyperFlow does take some extra attention and a bit of time to get to know it, but after years of developing this product, we feel confident that the extra attention delivers a high-performance payoff. If you have any specific product questions, please don’t hesitate to call 1.800.531.9531 to talk to someone in person.

Rating: 1 / 5

I just returned from a 7 day trip to the Sky Lakes Wilderness in Southern Oregon. Three of us had purchased MSR Hyperflow filters for the trip. We are all planning on returning them. Each of us had done some brief testing at home and all seemed well, but in the field all three were almost useless by the end of the week. One failed on the first day. It pumped 3 or 4 liters as advertised, but quickly became very hard to pump. It was back flushed, but this didn’t help. It could be used, but took a lot of pressure to pump and was very slow. The other two filters experienced similar problems throughout the week. We back flushed frequently, but the Hyperflows were all extremely hard to pump, and therefore very slow.

The filter element seems far too fragile for backcountry use. It can’t be frozen, and requires a lot of care. It is too bad because I love the design of this filter. It is compact and lighter than any other filter I have owned. Until the filter element is re-designed, I would not recommend this filter to anyone.

Edited by robhumphreys on 09/08/2008 17:18:37 MDT.

Rating: 2 / 5

Loved this pump at first. The lighter weight is ideal. Everything about it seemed ideal. But with several days use, the pumping became so hard, we soon dreaded needing to filter water. It is as if there is a vapor lock preventing pumping. Backflushing has not helped. This pump has become useless to us and unless there is a way to fix it, we will be returning it and going back to our other filter, which unfortunately weighs much more. ):

Rating: 1 / 5

At first I just loved this filter, it had all of the qualities of a good filter; fast pumping, compact, and light. I used it in the Sierra's, in clear water, following the backflushing instructions, and this filter was still USELESS after 2 days. I was in the middle of part of the Sierra High Route, which was fortunate for me that I didn't need to filter most of my water anyways. DON'T WASTE YOUR MONEY ON THIS FILTER!!

Rating: 5 / 5

I purchased one of the very first MSR Hyperflow filters from REI (April08) and experienced many of the filter issues that have been mentioned (reduced output, hard pumping, backflushing difficulties and the need to backflush more than the recommended amount). After contacting MSR (Nathan Hamm, consumer@cascadedesigns.com) and spending much time discussing the MSR Hyperflow he said that:
“We have been seeing issues with some of the filters which are prone to clogging and proper backflushing did not restore the expected performance. We are working with our suppliers to identify the source causing variations in the filter performance. Once we have resolved the problem I will send a free replacement cartridge to you.”
As promised I did receive the updated filter that performs 100% better than my original! It also has been brought to my attention at an outdoor equipment store I visited yesterday (24February09) that ALL of their MSR Hyperflow’s were RECALLED and they had just received the “updated” versions this past week. So for all of you that have filters purchased April 2008 – December 2008 I would check with MSR or the person you purchased the MSR Hyperflow filters from to see if you have an “updated” cartridge.

Rating: 1 / 5

My understanding from this and other sites is that this filter is not effective after thawing once the element has been frozen. If this is not so, it would be helpful to have this corrected. Otherwise, even with the updates, it will not be reliable. Below freezing temps are common at night, even in summer, all over the rockies, sierras and northeast.

Update - summer 2011: Purchased a new one based on the manufacturer's representations that the bugs had been fixed. Tried it out at my kitchen sink with prefiltered artesian well water, and found it to be the worst product I've ever seen. All of bugs mentioned here and more, such as the unbelievably poor directions. Thanks for giving hikers their worst nightmare, MSR!

Edited by scfhome on 07/13/2011 23:54:41 MDT.

Rating: 3 / 5

Just an update regarding the "Recall".

Received an email from Amber Wright, Consumer Services Rep. stating: "We have recently identified a flow performance issue with some of the hollow fiber filter cartridges...performance issue DOES NOT effect the product's ability to filter safe drinking water...issue has been rectified and all filter cartridges currently in production...perform to flow specification."

Enclosed is the phone # 1.800.531.9531. You will need to provide the microfilter serial number to receive a replacement if your filter qualifies.

Edited by arborrider08 on 03/25/2009 13:45:43 MDT.

Rating: 4 / 5

Thanks to these reviews mentioning the problems and the recall issue, I called MSR up and found out I had a problem element and I was mailed a replacement. I won't be able to determine how good it is until I do some spring hikes. I am encouraged that the brand manager for MSR is following these postings and responding to them.

Rating: 4 / 5

I've been tempted to buy this filter ever since it came out, and finally pulled the trigger a couple of weeks ago. I'm glad I waited for the kinks to get worked out of the element, because so far it has worked great for me. The advice I got from my REI salesman was to backflush a few pumps with every use, rather than waiting to backflush until after the filter's performance has already declined. This adds a bit of time and patience to the filtering process, but it still beats the pants off of my Miniworks in just about every way. Don't get me wrong -- there's nothing wrong with the Miniworks; the Hyperflow is just a more advanced technology.

I would hesitate to use it in sub-freezing weather, not only because ice would damage the element, but also because you have to get your hands wet fiddling with the nipples in order to backflush. On occasion I've found it a minor hassle plucking the smaller nipple out of the filter's body, but it hasn't caused me much frustration.

Another strategy that may help extend the filter's life is to filter from a collapsible bucket instead of directly from the stream. My prefilter doesn't rest well in my bucket, but I figure inhaling a little air is better than inhaling sediments.

Rating: 5 / 5

I used my MSR microfilter all summer on various multi-day trips and a 5 day trek through the Tetons. The filter performend perfectly and maintaintence was not really a problem and realitivly easy to do. It does clog a bit sooner then other filters, but the flow rate and weight of this little filer is outstanding. I really dislike the notion of adding chemicals to my water so this filter for me is the best to be had on the market to date.
At first I was a little leary of the apperance (it is a good looking filer to boot)of fragility of this filter, but it proved itself and is toughter then expected. It was beat up fairly good in my pack and dropped a few times accidently, and contiuned to work flawlessly.

Rating: 2 / 5

I purchased the MSR Hyperflow Microfilter in July, 2011 from a reputable store. My army buddy and I traveled to the Wichita Mountains Wildlife Refuge in Oklahoma for a weekend hiking/camping venture. On our first day the temperature hit 110 and we were depleting our water supplies quickly. The terrain was very difficult to traverse and the expenditure of energy was taking it's toll on both of us. My buddy fell and torn his rotator cuff halfway through the hike. First aid was administered and we pitched camp immediately. By the next morning we were down to 2 cups of water between the 2 of us. We had 6 more miles to travel to get help. The cell phones were useless. After all the water was expended, the situation looked bleak since the sun and temperature were steadily rising. We followed an old creek bed and eventually found a small pool of water. I broke out my new MSR Hyperflow Microfilter. Filling each bottle became increasingly more difficult to pump so after pumping 4 liters of water the unit became useless. Fortunately, the GPS got us back to safety. In summary, our situation was potentially life threating and we were dependant on a filtering system to get us through the weekend, The MSR unit failed us. If it had not been for the survival skills we had learned in the Army, things would gotten ugly. After returning home, I attempted to backflush the unit according to the directions. Despite trying 5 times, it was impossible to perform a backflush. All in all, I can not in good conscience recommend this unit to anyone until the research and development staff at MSR have resolved these problems.

Rating: 5 / 5

Carry less water in your pack and get a liter in under a minute? Sure! I got this in 2009, a bit after the kinks were worked out I suppose, and have never had a single issue with it. Except one time after I forgot to switch the valve back after a backflushing. That was my bad, though. Using this primarily in mountain creeks/streams has been great. It's so fast and simple. Even backflushing is easy. If I were to use it in murky water, I'd probably pre-filter with a bandanna around the "pre-filter" just to be safe, though.

Rating: 5 / 5

This filter is not for everyone. careful attention to detail must be made to insure the longevity and function of the device. I have had no real issues with this filter (except for the little red valve needing to be replaced, which was easy with the repair kit, after 2 years) also a great company to deal with.

Rating: 5 / 5

I've been backpacking and using filters/chemicals for 17 years. I also work at an outdoor retailer, so I see pretty much everything. Since I also get a good discount, I actually own a few filters. Personally, I own an MSR Miniworks EX, an MSR Hyperflow, and a Sawyer Squeeze Filter. My dad's had a Katadyn Hiker (actually an old Pur unit, but same thing) for 15 years or so, and I've used it hundreds of times. I've used MSR Miniworks in the field for years, and I've used pretty much everything else out there at least once. So far, the MSR Hyperflow is just incredible. Here's why:

1. SPEED! A full back and forth stroke takes about a second. It takes 20 to filter a liter.
2. Simplicity. No really. It all SEEMS so difficult with the back-flushing and all, but it's really not.
3. The pre-filter. This thing will suck water out of the sorriest water source on the planet.

Having said all that, this filter still scares me, and I'll carry backup for a few more test trips (Sawyer + Aquamira drops, about 5oz together). I just don't understand all the bad reviews. It worked flawlessly for me in some pretty crappy water. By the way, I bought this particular filter from a person on the internet who had issues with it. I got it cheap with a new filter cartridge.

I've only used it once so far, but it was used to filter about 20L over two days, and it seems most people have had problems by then if they had a bad pump. I experienced ZERO slowing or hard pumping. The source was a mountain spring at Oak Mountain SP in AL, and appeared to be fairly clear. However, it was a tiny trickle, and was only about 1cm deep, so even if it was nasty, it still would have appeared pretty clear. All the other water sources in the park were pretty cloudy and full of tannins, so it follows that my source was as well.

Had I used my Miniworks, I would have had to dig a hole and wait for it to clear just to be able to get the tip of the intake hose wet (same with a Katadyn Hiker). Had I used the Sawyer, I'd have spent an hour pouring 1oz of water at a time from my mug into the water bag. With the Hyperflow, I just set the pre-filter in the stream (it was so shallow the top of the pre-filter was not even getting wet, and the bottom was touching the dirt). It was the sorriest trickle of water I've ever seen. However, the Hyperflow sucked up the water like it was a roaring stream. I was worried since the pre-filter was sitting directly on the bottom, which was very fine, cloudy mud.

Day one, we quickly filtered about 9L (with zero slowing/clogging), then backflushed at the end. I only backflushed because the instructions told me to, not because of performance issues. The first 3 pumps of the backflush cycle showed significantly cloudy water coming out of the filter. It cleared up by the 4th stroke, and was perfectly clear by the tenth.

Day two, we repeated the above. No surprises, just pure filtering joy. I've never been so impressed with a filter. I PRAY that it keeps working so well. After backflushing once at home and twice in the field, it's stupid-simple. However, it REALLY helps to have a Nalgene and the supplied wide-mouth adapter. That assures you don't suck in air and cause an airlock condition. It's simple. Just start at the intake end, reverse valve one, reverse valve two, attach filter to clean water bottle with water, turn upside down and pump ten times. Turn valves back to normal position, and I'm back on the trail, when I would normally be halfway through filtering.

I will be taking it on two longer trips in the next 35 days, and will report back after those trips/tests. I will carry backup filtration/purification just in case. I am also going to figure out a way to use the filter body with my Sawyer filter cartridge (in case of filter failure). It shouldn't be hard. I might have to drill out a spare filter cartridge or something, or it might just be as simple as removing the filter (not sure if the filter body can still function without a cartridge in it, but I'll check tonight). I think the Sawyer cartridge with hose nipples (which I have) will make a great backup, and using the Hyperflow and pre-filter as a pump will keep the speed and flexibility intact.

I've heard MSR will be discontinuing this filter and moving toward gravity-based filtration (using essentially the same filter cartridge/HFM technology), but I'm sure they'll keep making the replacement cartridges.

I'm not sure why so many people have had issues, but I have my theories. One, the filter is actually crap, and I've just been lucky so far. Two, some people are not savvy enough to use this "complicated" filter. Three, once it starts slowing down/clogging, users respond by continuing filtering and pumping harder (at least until they hit the 8L mark, or fill their bottle). I actually saw some review where some guy was using his entire body weight to force water through the filter, and waiting to backflush until he hit eight liters. This pressure crams small particles deep into the filter fibers, and since backflushing is done with SUCTION (which can only achieve a fraction of the pressure of forward flow), it cannot remove the sludge that has been jammed deep into the filter fibers.

If theory three is the problem, the fix should be a simple early backflush, BEFORE it gets seriously clogged. Don't struggle to finish that fourth liter, or whatever, just STOP as soon as you notice slowing, and backflush. Yes, that's irritating, and could be time-consuming, but I have NO DOUBT that I could filter two liters AND backflush a Hyperflow before I could simply filter two liters with a Miniworks or Hiker. Crappy, filter-clogging water is rare. I'd take the extra backflushing 10% of the time to get the super-fast flow the other 90% of the time. That's assuming my theory/fix is legitimate.

I'll report back after I've had more time to evaluate the filter. I also personally know two people who have these, and have loved them after filtering many hundreds of liters. Sorry for writing a book, by the way.


A MONTH LATER:

So, since my last review and test, I've used the Hyperflow again. This time is was in North Carolina, in the Joyce Kilmer Slickrock Wilderness. For the first couple of days, the filter performed perfectly. No slowing or clogging was experienced. However, the last night, we were forced to use a very weak spring. I figured it would be a great place to put the Hyperflow to the test.

The water was clear, but it was just a trickle, and the ground over which the water was flowing had a very fine black silt. I dug a very small hole, and let it clear. The hole was just large enough to fit the pre-filter. Each time I would retract the filter (suction stroke), it would completely suck the little hole dry, even when going slowly. I knew I was getting all kinds of silty junk in the filter, but I kept going.

Around the 4 liter mark, I noticed the filter getting a little slow, so I stopped to perform a backflush. Normally, it takes about 3-5 backflush strokes before the expelled water is clear. This time it was about 8-9. After backflushing the flow was even worse than before, but still useable. It was clear that things were going downhill in a hurry. Instead of cramming more crap into the filter, I removed the filter cartridge, and installed a "blank" cartridge (which was an old one that I drilled out). Then, I installed my Sawyer Squeeze Filter (with attached hose nipples) about 3" from the Hyperflow outlet. This worked really well, and the flow rate was insane. I have no doubt that I could filter 5-6L per minute in this configuration (given adequate water flow, which this source lacked). This proved to be an awesome backup method, and only adds about 2oz to my pack.

Once I got home, I backflushed the MSR again, with similar results. I then decided to use the Sawyer faucet attachment to backflush the MSR filter with full faucet pressure. This restored it to full flow again (as far as I can remember). I still love the filter, but realize that it's too finicky for backcountry use without a backup. I will continue to carry it, but with the Sawyer as a backup. That way, I still get the fast flow and the ability to suck water out of the smallest little puddle. I am convinced the problem is that backflushing with suction just can't remove the junk that gets crammed into the filter. I will also start using an MSR Siltstopper from now on. Hope this info helps, and I'll check back in about a month when I have more info. I'm taking 7 other people up to TN/N.C. the beginning of June, and we will be using this filter (among others).

Edited by Zolen on 05/15/2012 20:50:47 MDT.

Rating: 2 / 5

I really tried to like this filter. It is awesome for the first 10 gallons or so. After a couple months of light use(about one overnighter a month), the original filter element crapped out and the unit became essentially un-pumpable. After consulting with MSR, I purchased a $40 replacement element and assumed a religious regime of back flushing a liter for every 3-4 liters filtered. Despite the regular back flushing, after about 10 gallons, the pump still filtered, but it became incredibly difficult to pump water. I'm not willing to work that hard to pump water after a 20 mile day :(