MSR SweetWater Purifier Water Filter Review

The MSR SweetWater Purifier Water Filter System is a hand pumped water filtration system that filters and purifies drinking water from backcountry water sources. Even though crystal clear flowing streams and lakes may appear clean lurking within them may be microscopic parasites invisible to the naked eye. The [easyazon_link identifier=”B000BBF2UG” locale=”US” tag=”allaroundcamping-20″]SweetWater filter[/easyazon_link] is designed to remove harmful microbes such as bacteria, viruses, and protozoa from any water source and provide clean drinkable water to keep outdoor enthusiasts hydrated and safe during backcountry excursions. With safety and efficiency in mind the filters pumping system provides a distinct mechanical pumping advantage and quickly unhinges for compact storage.

MSR SweetWater Purifier Water Filter Features: 

  • With a silica depth, sodium hypochlorite coated filter media the 0.2 micron pore size openings meets U.S. EPA requirements for microbiological water purifiers and is certified to NSF protocol P231. This designates the system is capable of removing 99.9999% of bacteria, 99.9% of protozoa, and 99.99% of viruses through the entire life cycle of the filter.
  • While the SweetWater micro filter removes bacteria and protozoa, the chlorine base purifier solution provided must be administered to remove viruses in the water. Contrast to other chemical based purifiers the chlorine based solution does not leave a bad taste. Many backcountry water sources do not contain viruses but in spots where fecal matter contamination may be an issue it is best to use the SweetWater Purifier Solution.
  • The pump lever action handle provides a 4 to 1 mechanical advantage that allows water to be pumped with each up and down stroke. This allows an optimal flow rate of 1 liter per min minute for approximately 75 strokes of the pump.
  • The entire system weighs only 14 ounces saving precious weight in your pack. The pump handle can be quickly disassembled to fold flat along the filter body to condense the unit for easy storage.
  • The stainless steel pre-filter strains any larger particulate from the water source before entering the main filter.
  • A foam float keeps the pre-filter apparatus from contacting the bottom of the water source (stream or lake bed) and disturbing any sediment.
  • The clean water outlet tube comes with an attached bottle adaptor to fit on several different water container opening sizes and prevent any spillage.
  • Each filter cartridge is rated to clean 750 litters of water, however this depends on the level of contamination in each water source. Once the flow is considerably reduced and the metal meshing is visible on the filter housing the filter should be changed.
  • For quick cleaning in the field a brush is included to clean out any debris that may block the filter and reduce water output. In cases where the filter becomes blocked a relief valve opening is designed into the filter body to allow pressurized water to escape and avoid any damage to the unit.


  • The filtration system is very easy to clean in the field. Once the flow of the pump is decreased and you are discharging a fair amount of water from the relief valve this is indication the filter needs to be cleaned. Just remove the filter cartridge and brush the inside to remove contaminants, reinsert the filter, then back to full flow. The filter can be cleaned many times before replacement, though it is recommended not to over brush to prematurely wear the filter.
  • The carbon filtered water has been noted to be good tasting even with the chlorinated drops.
  • For ultra-light backpackers and those in small groups the size and weight of the unit is optimal. At under a pound and small enough to fit all components into a palm sized sack the benefits of bring the filtration system along to provide clean water more than makes up for the added weight to your pack.
  • Simple assembly and disassembly, two rubber hoses inserted over nipples clearly labeled In and Out ports. Quick rotation of a small set screw for the handle and you are ready to pump fresh water.
  • With its two way action, discharging water with both up and down strokes, it speeds up the process even though 1 liter per minute may seem a bit slow. Though the pump action may seem a bit awkward at first once you are familiar with its operation it becomes quite simple.
  • The water bottle adapter on the discharge hose can fit a variety of bottles and hydration packs, making sure no filtered water is wasted.
  • For about $100 the unit more than pays for its self. Replacement filters typically cost $40.


Providing safe, clean drinking water on backcountry excursions is paramount to any backpacker’s trip. When used correctly the MSR SweetWater Purifier Water Filtration System protects against harmful microbes that would otherwise cause an enjoyable trip in the wilderness to be ruined by sickness. I have used the [easyazon_link identifier=”B000BBF2UG” locale=”US” tag=”allaroundcamping-20″]SweetWater System[/easyazon_link] myself on several hiking trips and have never been sickened by fouled water. However, there are a few design flaws which do limit its use. Explained below are some the limitations and concerns to be taken into account when considering this filtration system.

  • The pre-filter attached to the inlet tubing can become clogged when dealing with a large amount of sediment. Several solutions to limit sediment intake would be to attach a coffee filter with rubber band to the pre-filter. Also, removing the sediment laden water for its source and letting the sediment settle to bottom has also been reported to work. MSR does sell a SiltStopper pre-filter system that attaches to the inlet hose for about $20 and increases the life of the main filter. If you are pumping from silty water on regular basis it will shorten the life of the filter no matter what and should be taken into account on long trips.
  • Due to the amount of time it takes to pump clean water, 1 liter per minute, it is time consuming for a large group of hikers. The SweetWater system is better suited for single hikers or small groups.
  • Due to the awkward pumping motion of the handle and is plastic construction several users have reported the handle breaking. Though part of the pin holding the handle to the pump is metal a majority of the construction is plastic. Any blockage on the filter or in the suction and discharge line may cause a buildup of pressure and cause difficult pumping.
  • Using the filter alone only removes bacteria and protozoa. The chlorine drops provided with the kit are required to remove any viruses. As far as any environmental or chemical contamination, such as that from farm pesticides, the filter system does not protect against them.


Consumer feedback

The overwhelming majority of consumers who purchased and field tested the [easyazon_link identifier=”B000BBF2UG” locale=”US” tag=”allaroundcamping-20″]MSR SweetWater Purifier Water Filter system[/easyazon_link] gave it a positive reviews. Most user users gave it the highest rating possible and remarked how they would recommend to system to others. It was often glorified for its ease of functionality and ability to keep them safe from illness causing microbes in backcountry water supplies.

Its lightweight design compared to other filtration systems was a contributing factor for making it a key piece of backpacking equipment. Users also commented on its compact design and ease of assembly with few parts needed to be assembled and reassembled for use. The only major complaint repeated was the handle’s less than robust construction which lead to it breaking for a couple of users. Though the manufacturer was responsive and replaced the unit each time.

Due to its low base price and replacement filter cost the SweetWater Filtration system is a bargain. With relatively few negatives it provides safe dependable drinking water for the intrepid wilderness adventurer.

MSR SweetWater Purifier System

as of April 17, 2024 6:54 am


  • Iodine-free Inactivates viruses without bad-tasting iodine.
  • Easy to Use Lever-action pump handle has a 4-to-1 mechanical advantage and dual pump action, so you don't have to work as hard.
  • Dependable Inactivates 99.99% of waterborne viruses; eliminates over 99.9999% of all waterborne bacteria and 99.9% of common protozoan parasites, such as giardia and cryptosporidia, as well as particulates, bad tastes, and odors.
  • Lifetime warranty