How does it accomplish this? On each stroke, the Guardian self-cleans by using 10 percent of its water to flush out contaminants in the filter, meaning you don't need to hassle with constantly cleaning the cartridge to maintain flow. Even when our only choice was murky water, it never got blocked with silt or slowed in flow.
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As a true test, on our first night bikepacking in Peru’s Cordillera Blanca range, we pumped and drank from a creek where a full cow skeleton had come to rest and did not get sick. In fact, the Guardian is such a reliable and convenient system that it’s now being used as an emergency water purifier after natural disasters and in less-developed countries around the world.Īside from easy setup and filtering, another selling point of the MSR Guardian is the lack of maintenance.
A quick overview here: water filters do not remove viruses (pumps from brands like Katadyn and MSR only protect against protozoa and bacteria), while water purifiers (like Aquamira drops) do not filter sediments or particles from water. But the MSR Guardian offers the best of both worlds by allowing you to both filter and purify water simultaneously-the ultimate peace of mind when backpacking in high-use areas (viruses are most commonly carried in human waste).
While the Guardian is extremely easy to use, its true claim to fame is in its hybrid filtration and purification functionality. We did have some issues keeping the intake hose under the water-it tended to flip and float to the top when left in both flowing and still sources-but with a little fussing, we learned that lodging it against a rock was an easy solution. Because it was so simple, we ended up using filtered water for everything we did on our trip, including washing dishes. We typically filtered four liters at a time, which took about three or four minutes (the Guardian claims it can output about 2.5 liters per minute, but we always find manufacturer claims to be a bit ambitious or require perfect circumstances). Once water began moving up the hose, we were immediately impressed by how fast the Guardian worked. All we had to do was unscrew the cap and attach a Nalgene (or hold it overtop of a different size bottle or reservoir), drop the intake hose into a water source, and start pumping. The MSR Guardian was extremely easy to set up and use, even on the first go. To see how it stacks up, see our article on the best backpacking water filters and purifiers. Below, we break down the Guardian’s setup and functionality, maintenance, weight and packability, build quality and durability, and more. While definitely not the cheapest or lightest option on the market, we think the added cost and ounces are worth it in the right situations. We took this unique hybrid filter and purifier along to Peru’s Cordillera Blanca and Mongolia’s central mountains, and came away extremely impressed with its ease of use, lack of required maintenance, reasonable weight, and superb durability. MSR has been a longtime leader in backcountry water purification, so it’s no surprise that their Guardian has become our go-to pump for big trips abroad.