Lightweight Water Filtration

Pump it, stir it, nuke it, suck it. Yep, there are plenty of ways to make clean water; each with their pro’s and con’s. The following setup is low tech, doubles as a hydration pack, and provides a means of caching up to 6L of water with one trip to the water source. It’s not the absolute lightest option, however at 12oz it is a lightweight system and I believe it represents the best in tradeoffs between weight, utility, and convenience.

The Purchased Bits

All of the parts needed to put this system together are included with these four items. Pick them up from your favorite gear shop:

  • Sawyer “3-Way” filter kit
  • Platypus 4L “Water Tank”
  • Platypus 2L “Hoser “
  • Platypus drink tube kit
Sawyer 3-Way Filter Kit
Sawyer 3-Way Filter Kit

Platypus Water Tank
Platypus Water Tank
Platypus Hoser
Platypus Hoser

Platypus Drink Tube Kit
Platypus Drink Tube Kit

The Dirty Water Tube

To make the dirty water tube you’ll need most of the parts from the drink tube kit as well as a male quick disconnect fitting from the Sawyer kit. One end of the tube has a Platypus cap on it, the other end has the male fitting. Done.

Dirty Water Tube
Dirty Water Tube

The Clean Water Tube

To make the clean water tube you’ll need the tube assembly from the Hoser and a female quick disconnect fitting from the Sawyer kit. Cut the bite valve off leaving an inch or two of the drinking tube attached to it, set this aside. Put the female fitting on the end where the bite valve was. The Platypus cap should already be on the other end. Done.

Clean Water Tube
Clean Water Tube

The Bite Valve Tube

To make the bite valve tube you’ll need the bite valve that you cut off from the Hoser drinking tube, the short piece of tubing you left attached to it, and a male quick disconnect fitting from the Sawyer kit. Put the male fitting on the end opposite the bite valve. The bite valve cover is optional. Done.

Bite Valve Tube
Bite Valve Tube

Putting it All Together

Did you successfully make all of the pieces above? Good job, you’re truly the master of your domain. Ok, moving on… your 2L Platy serves a dual purpose here. It’s both a hydration system and clean water storage (CWS) for in-camp. Remove it from your pack and prop it against a rock, tree, your buddy’s leg… whatever, so long as it’s at propped up with the cap on top. Uncouple the bite valve using the quick disconnect and hook up the Sawyer filter. If you have your fittings correct you should only be able to connect the CWT to the “clean” side of the filter.

The 4L Platy is your dirty water tank (DWT.) Fill it up and cap it with its closure cap then carry back to camp. Once in camp and ready to filter, connect the end of the dirty water tube to the Sawyer filter (again you should only be able to connect the DWT to the “dirty” side of the filter) then uncap the DWT and hook up the dirty water tube. Don’t lose your water tank closure cap!

Put the DWT on something that’s above the CWS. The greater the difference in height, the faster the flow. Water should begin to flow right away. It helps to slightly loosen the cap on your CWS so air can escape as it fills with water – just don’t forget to check on the progress after a few minutes otherwise you might lose some water on the ground. For that reason it’s probably best to avoid filtering water with the CWS in your backpack or on other gear that needs to stay dry. Murphy’s Law prevails. That’s all there is to it. When you’re done filtering put the bite valve back on the CWS, suck the excess water through the (clean side of) the filter and put it away.

Making Clean H2O
Making Clean H2O

This system has a few things going for it…

  • It’s lightweight
  • No chemicals needed
  • No pumping or stirring needed
  • Allows for multi-tasking while water is filtering
  • Serves dual purpose as water filtration and drinking system
  • Strategic use of fittings prevents accidental mixing of clean and dirty components
  • The removable bite valve makes thread the drinking tube through any backpack hydration port easy.
  • Can cache up to 6L of water in one trip (2L filtered, 4L unfiltered)
  • It’s low tech with very little that can fail

The Con’s

  • There are always 1-2 loose components that could potentially be lost
  • The filter must be protected from freezing (as with all membrane filters

The Ounces

The weight breakdown on the individual pieces goes like this (actual weights on my scale):

  • 4L Platy Tank = 3.70 (1x)
  • 2L Platy Hoser = 1.45 (1x)
  • Platy Tube (bare) = 1.70 (2x)
  • Platy Bite Valve = 0.25 (1x)
  • Platy Cap with hose barb = 0.15 (2x)
  • Sawyer SP122 = 2.70 (1x)
  • Sawyer male fitting = 0.10 (2x)
  • Sawyer female fitting = 0.15 (1x)

Total out of the box is 12.05 oz. On my setup I trimmed the tubes slightly and it weighs in at 11.5 oz. The Platy tubing is rather heavy; I’m sure lighter tubing exists and this setup can probably be brought down to 10 oz or less but I have not been able to bother myself in spending the time or energy to source such tubing. A drinking system, filter and water storage for 11.5 oz is a good weight as far as I’m concerned. If, for instance, you’re carrying a Katadyn Hiker Pro filter, 1L Nalgene bottle, and 2L Camelbak this setup give you the ability to cache twice the volume water and drop over a pound from your pack! Hike It. Like It.


  1. You’ll have to slightly molest the Sawyer kit in order to make use of all the fittings needed. Some of them come pre-attached to other pieces such as an adapter tube and a back-flush adapter. No big deal to pull them off and re-attach as shown above.
  2. The astute reader will notice the bite valve and cover are the Camelbak variety. I prefer these over the Platypus bits because they’re smaller, lighter, and easier to drink through.
  3. Yes, the dirty water tube can be made shorter, but a longer tube means more pressure pushing water through the filter and faster filtration.
  4. Ok, you could use a 2L platy for the DWT but the 4L is easy to fill due to the wide opening, also easy to clean, and the obvious… it holds more water.


This setup worked well for us for several years but change is inevitable. We were able to find three reasons to switch things up.

  1. A lighter option existed.
  2. The ziplock closure on the 4L Platy has become very stiff with age making it a PITA to get closed.
  3. We want to be self sufficient rather than sharing gear.

Have a looksee at this post for the details of what we’re doing these days for water filtration.

Jacob D Written by:

Jacob is the head honcho, wearer of many hats, and modern day berserker here at Hike It. Like It. When he's not out hiking or running the trails you'll find him operating in full capacity as a Super Dad and chipping away at a degree in Kinesiology. This guy likes to stay busy. Follow on Strava


  1. best of venice florida
    July 29, 2014

    First off I want to say wonderful blog! I had a quick question which I’d like
    to ask if you don’t mind. I was interested to know how you center yourself
    and clear your thoughts prior to writing. I have had trouble clearing my mind in getting
    my ideas out. I truly do enjoy writing but it just seems like the first 10 to 15 minutes tend to be wasted just trying
    to figure out how to begin. Any suggestions or tips? Kudos!

    • July 30, 2014

      Hi and thanks for taking the time to leave such a thoughtful comment with a Kudos even!

      Let me address your question… usually I just sit down at the keyboard with a cup of tea and an idea. Sometimes that doesn’t work though, like most of the time. In those cases I will generally start by putting on some Burning Spear and firing up a tree-sized blunt. Right before I get completely mellow I plow though a few lines of blow and have a crazy tickle fight with my cat. After bandaging up all the scratches I sit back down with a cup of tea, then repeat as needed. Hope that helps!

  2. […] couple of years ago I posted an article about the lightweight water filtration setup that Sandra D and I were using at the time. Up until recently we’ve been using that same kit, […]

  3. Kathleen
    June 18, 2013

    Hello! I just wanted to ask if you ever have any issues with hackers?
    My last blog (wordpress) was hacked and I ended up losing a few months of hard work due to no data backup.

    Do you have any methods to stop hackers? Thank you so much, a wonderful job!

    • June 22, 2013

      No problems. I just eat them. They taste like fruity pebbles.

  4. taylor
    August 4, 2011

    What is the tube size you are using here? I lost my filter tube and need to make a replacement, but I’m not sure what size to get.

    • Jacob
      August 5, 2011

      Taylor, the tube is 3/8″ outside diameter with about .063 inch wall thickness. Let me know what you find, especially if its lighter than the stock tube! 🙂

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