MSR Guardian Purifier Review

The MSR Guardian is our favorite hand pump and one of the most reliable options out there. Although it's a little bulky and very expensive, it's super easy to use and filters out everything from bacteria to viruses. This purifier can be used anywhere in the world, filtering out the meanest microbes to keep you healthy and happy while traveling internationally or heading into the backcountry. It can't, however, remove heavy metals or chemicals.

Performance Comparison

The Guardian Purifier is at home anywhere in the world. Here we use it in the pristine alpine meadows in the Sierra Nevada. While this technology is a little overkill for this environment, it's a great option for travel abroad in developing nations.

Photo: Jessica Haist

Water Quality

This purifier comes with a kickin' filter with a pore size of 0.02 microns. Most filters in this review only have a pore size of 0.1 - 0.2 microns, but this one is capable of filtering out bacteria, protozoa, and viruses. The filter has a hollow fiber design and produces water that is clean, healthy, and tasty.

The Guardian's unique hollow fiber filter.

Photo: Jessica Haist

Unfortunately, because it doesn't have activated carbon, it doesn't remove chemicals, heavy metals, or odors. However, we are impressed that it's the only model that can stand up to the most turbid streams. This model is excellent for international travel or backpacking with one to two people.

Durability and Maintenance

This water filter is exceptionally well-constructed and quite durable. Not only has it been drop tested up to six feet on concrete, but it can withstand freezing temperatures! Maintenance is minuscule. Every time you pump the filter, it is continually self-cleaned with every stroked. Unlike other models, the filter doesn't get clogged easily, even in turbid water.

This bomber design is highly reliable. The filter itself will last up to 10,000+ liters, which is far more than any of the gravity filters that we've tested. Of the purifying systems, this has by far the most extended lifespan that we've seen that can remove viruses. If a reliable and well-built machine is what you're after, this handpump is our favorite — self-cleaning, low maintenance, with a wide range of applications.

Treatment Time

In comparison to other hand-filters, this is the fastest, and one of the fastest filtration systems, period! After many trials, it produces, on average, one liter in 37 seconds. Overall, you don't have to worry about the filtration process taking forever. It's quick and easy to use. This treatment time slows a bit in turbid water, but it offers consistency in treatment, unlike any other system.

We are surprised how easy and fast the MSR Guardian is to pump.

Photo: Jessica Haist

Weight and Packability

While this purifier is super fast, providing amazing water quality, it's heavy and pretty bulky. Weighing 1 lb 4.50 oz, it's one of the heaviest filtration systems out there. In terms of its volume, it's rather bulky and is a little larger than a Nalgene bottle. We like that it doesn't have a lot of loose parts and comes packaged nicely in its included carry case.

While this is not the lightest system, it still packs down relatively small. Here we see comparisons with the Katadyn Light Hiker, another hand pump that doesn't filter out viruses.

Photo: Amber King

Ease of Setup

Setting up this filter is easy. In the box, it comes with all parts together and intact. There are no loose parts that you might lose. Pull it out of its pouch, take off the cover, and place the hose in the water for direct filtration.

The handpump setup allows you to direct the intake hose to any water source. It works well in medium-size water sources, but can also be used in small puddles or hard-to-reach areas like steep banks or off the side of a boat. The hose also features a mini-filter screen that will sift out larger particulates, so your hand pump filter doesn't need to deal with algae or debris sitting in the water — it's pre-filtered first.

The Guardian has no assembly required, is simply to use, with some key engineering that makes filtration easier.

Photo: Jessica Haist

Ease of Filtration

As a handpump, it's not hard to use at all. The large handle is super easy to grab and the cartridge body provides another place to hold the pump firmly. When pumping, the high flow output easily sucks water and pushes all of it out in one cycle. Of all handpumps we've tried, it's one of the easiest to use, making filtration nice and easy.

Pumping purified water into a wide-mouth Nalgene works well.

Photo: Amber King

The only real issue we've come across is that sometimes the intake hose's float gets turned around in the water source, and sucking becomes less efficient. Therefore, you need to watch and make sure that it is in position for the most efficient pump action. It may also present a problem in shallow or small water sources because the float is quite large. Also, this pump comes with a bottle top adaptor that fits most wide-mouth water storage containers. You can also easily screw on a Nalgene bottle to the bottom of the filter. If neither of those work, pump into your water storage container.

While this is a smooth hand pump to use, hand pumping in general kind of sucks. Hand pumping requires a lot of effort, forces you to sit in one spot and not accomplish other tasks around camp, and can take a while. While it does provide an excellent output, if you can swing it, a gravity filtration setup is preferable and is a lot less work. But, it can't access the same hard-to-reach water sources.

Value

So now that you've fallen in love with this filtration system, we're going to offer a kick in the pants: the price. It is the most expensive filter or purification system in this review. Most people don't have this kind of cash to throw down on a system that purifies water. That said, the investment is worth it for the durability of the product. Don't expect to buy another one for your lifetime. If you're a guide or a service looking for an option that will continue working for you, this model is good for multiple uses. And with its ease of use, it works for anybody. Since its niche is in its ability to filter out viruses, which we don't require in North America, there are better options for a much better price if you stay stateside. That said, in the long run, value is actually pretty good given that replacement cartridges rarely need to be bought and no maintenance is needed.

The Guardian is a great choice for group trips, especially international ones where virus-contaminated water is an issue.

Photo: Jessica Haist

Conclusion