Reader Reviews

Rating: 4 / 5

This Filter weighs in at 2 oz and once installed it has a very small impact on flow rate from the hydration tube/bite valve. I'm using it in conjunction with a Platypus hydration setup and you get an extra bonus of being able to slip off the hydration bite valve from the platy and use this as a gravity filter.

This filter does require a screwdriver to install the metal hose clamps that secure it inline. This, in my opinion, makes this filter non-servicable in the field. It also has a positive backstop for flow, meaning that you can not backflush the filter in the field either.

Still, for 2 oz, in many of the area's I hike, this is very light protection.

Rating: 4 / 5

I just installed a Sawyer Inline on my Platy Big Zip and I'm very, very impressed by the flow. I can drink from the hose and barely notice any difference. If their claims are accurate about what it filters this is an amazing little treatment device for all but viruses. Unfortunately, unlike ceramic core filters, there's no way to clean the filter element. So it gets a 4, not a 5 (actually, I'd give it a 4.5 if I could).

The unit comes with hose clamps, but in my opinion they're overkill. An adequate seal is made by just pushing the tubing up far on the nipples.

One open question is backwashing. The Sawyer website says "... faucet adapter can also be used to backwash and extend the life of your filter." REI's website says "five hundred gallon usage is dependent upon using reasonably clean water and backwashing if flow begins to slow."

But the USACHPPM says it's not backwashable (http://chppm-www.apgea.army.mil/WPD/WPDSHARE/193/AddInfo_SawyerInlineFilter.pdf). I'm not sure where that comes from. I just took mine apart and I see no evidence of a one way valve.

The product literature that comes with the Sawyer does say that if you get the flow backwards you'll decrease the life of the filter. But that likely just means that you should be careful not to push dirty water the wrong direction. If you look at the diagrams on Sawyer's website, it looks as if dirty water going the wrong way would force particles into the ends of the hollow fibers and plug them up.

Edited by jiry on 03/03/2007 15:12:21 MST.

Rating: 4 / 5

Pros: Light Weight, Field Cleanable by backwashing, No Chemicals, No Pumping

Cons: Setup time longer than traditional filter. Speed of filtration can vary based on conditions. Like traditional filters, susceptible to damage if frozen. No way to test or verify that the filter is working or not.

5/27/09 Update: I have revised my rating to a 3.5 due to the fact that there is no way to test or verify that the filter is working or not. My other concern from other filters that use this same technology is that they may clog up with muddy to silty water.

Warning: Do Not allow any type of filter to freeze. Drain completely when done. Sleep with filter in your sleeping bag, if necessary to prevent freezing. Alway carry water treatment chemicals as an emergency backup in the event your filter fails.


Videos & Links to Sawyer Explaining System & Technology


Master List of Videos:

http://www.sawyeronline.com/videos.htm#vidwater


General Overview of Sawyer Filters & Technology:

http://www.sawyeronline.com/Video_Introduction.html


Specs & Status for Sawyer In Line Filter:

http://www.sawyeronline.com/SP121.htm


How to Backwash Filter at Home & In the Field:

http://www.sawyeronline.com/Video_Backwashing.html


One Million Gallon Filtering Guarantee:

http://www.sawyeronline.com/Video_Closing.html



My experience:

I now use the Sawyer inline filter as my sole water filtration system for my family and I, including my four year old daughter.

My first experience using the Sawyer inline filter was on a backpacking trip to Lake Vernon in May 2007 in Yosemite above Hetch Hetchy Reservoir.

Conditions were bad with rain turning to snow at the higher elevations. We were forced to retreat back half way into the trip when snow levels reached knee high levels and my wife had earlier fallen and injured her leg. We retreated to a area that had snow on the ground at levels of two or three inches, where we could pitch our tents.

Our only source of water was a small, stagnant pond that was choked with fallen trees and decaying grasses all along the shoreline. The water along the shoreline was shallow, green in color and choked with small bits of debris in the water.

In our group of four, only one of us had a traditional filter, a MSR Sweetwater Micro filter. After pumping about 3/4 of a Liter, the filter complete clogged up and failed. Unfortunately, the person who had brought the filter had forgotten to bring the cleaning kit for the filter!

I pulled the gravity filter out and assembled it, hoping that it would work as advertised. In my dirty water bag of green water, I could clearly see bits of dead grass and a few small bugs swimming around.

To my surprise, the filtered water still had a greenish, brown color to it. With some reservation and skepticism, we drank the water and cooked with it. What other option did we have? Thankfully, the filter worked and no one got sick during the remainder of the trip or afterwards.

I estimate that each one of us easily drank three to four liters of water filtered by the Sawyer inline filter.

Since that experience, the Sawyer filter has been the only filter that I use.

Recent trips with the Sawyer filter:

4 day, 50 mile loop from Yosemite's Glacier Point to Red Peak Pass at 10,800 ft to Merced Lake, Little Yosemite Valley, back to Glacier Point.

4 day, 70 mile trip on the High Sierra Trail from Crescent Meadow to the top of Mt. Whitney.


Here is the list of items that you will need:

* Sawyer In Line Filter 1.80 oz
* Platypus Filter Link 0.50 oz
* Platypus Water Tank 4 Liter 3.0 oz
* Platypus 2+ Liter Water Bottle 1.20 oz
* Nite Ize Figure 9 Rope Tightner Small Size 0.25 oz
* Kelty Triptease Guyline/Cord 3-4 ft. 0.10 oz
* 3ft. 3/8" Food Grade Vinyl Tubing 3.50 oz
* 2 3/8" Metal Grommets 0.25 oz
* Grommet Tool for installing grommets

Total Weight of Full System: 10.6 oz

****NOTE: AS OF 2009 Cascade Designs, makers of Platypus discontinued production of the Filter Link, as they are now selling the Clean Stream Gravity Filter System****

****An expensive solution to this is to purchase the replacement threaded tubing for the hydration system system and cut it short to substitute for the Filter Link*****

****As of 2009 Sawyer now offers a Gravity Filter System. However, it appears to be a much heavy system than described here****

Weight of Stripped Down System: 5.3 oz
(See Below for details)

Weight of Trail/Dayhiking System: 3.3 oz
(see Below for details)

What is inside the filter?









Here you can see the strands of the hollow tubing that have been arranged in a U shape.



The ends of the hollow strands are embedded in a resin, which allows only the clean water that is filtered to exit out through the cut ends. Note: If you look carefully, you can see the inconsistency in production. Some of the hollow tubes are still embedded in the resin, which prevents filtered water to exit. The vast majority are resin free and able to allow water to exit. I wonder if this creates any sort of measurable variable between filters on performance on speed of filtering?

How to Build Sawyer Gravity Filter:

1. Identify top and bottom of Sawyer Filter: Top of filter is the input for dirty water. Bottom is output for clean water

2. Attach Tubing included with Sawyer Filter to "top" of Sawyer Filter

3. Secure tubing to Filter with hose clamp included with Filter

4. Attach Platypus Filter Link to open end of tubing

5. Install one grommet at the left side of the bottom edge of the Platypus Water Tank

6. Install one grommet at the right side of the bottom edge of the Platypus Water Tank

Note: When the Water Tank is standing upright on a table the grommets should be facing towards you, not underneath the Water Tank. Grommets are for hanging Water Tank upside down using cord from a tree branch or tree trunk





How to use Sawyer Gravity Filter:

1. Fill Water Tank with Dirty Water

2. Seal "Zip Lock" top of Water Tank

3. Make sure that threaded cap included with Water Tank is tightly installed

4. Thread Cord through both grommets

5. Hang Water Tank upside down from a tree branch or tree trunk using Cord

6. Using Nite Ize Figure 9 Rope Tightener to quickly tie or untied cord to tree branch or tree trunk

7. Attach 3ft. 3/8" Food Grade Vinyl Tubing to the "bottom" of Sawyer Filter

8. Stand Platypus 2+ Liter Water Bottle Upright on the ground

9. Lift hanging Water Tank to upright position and remove threaded cap

10. Screw on Filter Link/Sawyer Filter to Water Tank

11. Lower Water Tank to the Hanging upside down position

12. Start filtering process by sucking on end of 3 ft. Food Grade Vinyl Tubing until water flows through filter

13. Insert end of 3ft. Food Grade Vinyl Tubing into Platypus 2+ Liter Water Bottle to collect clean, filtered water

14. When Platypus 2+ Liter Water Bottle is full replace with an optional second Water Bottle to filter remaining water in Water Tank

15. If you only have one Water Bottle, unscrew Filter Link/Sawyer Filter and thread cap onto Water Tank

16. Filter additional water as needed

Note: For additional convenience, a second Platypus Filter Link can be attached to the end of the 3ft. tubing and threaded to the Platypus 2+ Liter Water Bottle. If this is done, thread Filter Link loosely to allow air to escape from the 2+ Liter Water Bottle. Failure to do so will result in pressure accumulation in the Water Bottle and will slow or stop water flow to the Water Bottle.

Note: As you become more proficient at using the gravity filter, you can attach the Sawyer filter to the Water Tank before hanging the bag upside down from a tree.


How to save weight using Stripped Down System:

1. Only use Sawyer Filter, Platypus Filter Link, and Platypus Water Tank

2. Use your hydration system as your "catch bag" for clean water

3. Remove bite valve from hydration system

4. Connect bottom of Sawyer Filter to your hydration system's hose where bite valve was attached

5. Lay Water Tank on its side on a rock or fallen tree vs. hanging from a tree branch or tree trunk

Note: I use a Platypus 1.8 L Hoser Hydration System (3.5 oz), which has a gusseted bottom that allows it to stand upright.

When using the Hoser as a catch bag, it is important to loosen the threaded cap that connects the tubing to the hydration bag to prevent pressure accumulation, which will slow or stop the flow of water.


How to use Sawyer Filter on the Trail or Day hiking:

1. Only use Sawyer Filter, Platypus Filter Link and 1 oz. disposable 1 pint/500 ml water bottle

2. When hiking on the trail and you want a fast drink of water without having to use the full system, fill 1 pint bottle with dirty water

3. Screw on Filter Link/Sawyer Filter loosely to 1 pint bottle

4. Turn bottle upside down

5. Use bottom of Sawyer filter as a straw to suck water from bottle through filter



Note: Loosely thread the Filter Link/Sawyer Filter. As you drink water, you should see a steady stream of air bubbles rising in the bottle.

Threading the Filter too tightly to the bottle will create a vacuum as you drink, which will collapse/crush the bottle and slow the flow.

Seeing the air bubbles rising in the bottle is an indication that you have not threaded the Filter too tightly.

***Storing filter after use: I recommend using your mouth to suck on the clean water output end of the filter like a straw to drain the filter of all water, which decreased the wet weight of the filter and decreases the chance of damage due to possible freezing***

I hope that this helps you to lower your pack weight and help you to build a gravity filter using the Sawyer Inline filter.

-Tony

Note: Regarding Backwashing filter to clean in the field.

I have not experienced a reduction in water flow while in the field.

Each time that I have returned from a trip I have backwashed the filter using the gravity filter system using a small cap full of bleach followed by rinsing the filter two times with clean water.

Based on my experience at home, I see no reason why I could not backwash the filter in the field.

Update: 12-03-08

I have now been using this filter for over 1.5 yrs without suffering any illness or decrease in performance/rate of flow. I have also never needed to back flush this filter in the field.

I do back flush the filter at home after each trip before storing it between trips using warm water with about 10 drops of bleach in 1 to 1.5 liters of water.

Sawyer now offers a life time guarantee on this filter.

There are two negatives that I have found with this system:

It does not have an active carbon component to it to filter out the taste of bad water.

The imperfect solution that I have come across is using a Katadyn accessory that is also an inline product, but filled with active carbon. This works well, but is bulky/heavy.

The other negative with this system is the Platypus Water Tank. The zip closure is very difficult to close and almost impossible to close if your hand are cold and wet. Very frustrating. I hope that Platypus will come out with an improved version of this useful bag to address this problem. Perhaps similar to the redesigned Big Zip's closure system.

****Update 3/29/09: Platypus came out with a new and improved water tank closure system which looks like it will take care of one of the major problems plaguing this system****

****Update 07-20-09: I used this system for 9 days while hiking the 168 mile Tahoe Rim Trail and did find that after 6 days of use, the rate of filtration decreased dramatically- almost to a trickle. I back washed the filter by simply rolling up my clean water Platypus bottle and applying quite a bit of pressure to reverse the flow of water in the gravity filter system. I only need to push less than a cup of water through the filter to clear it. I was surprised by how much force was needed to backwash the filter. I was even concerned that I might damage my clean water Platypus bottle, due to the amount of force/pressure needed to backwash the filter. Once the filter was cleared, the filter's rate of filtration was back to normal and was good for the rest of the trip. In hind sight, I should have paid more attention and noticed the steady decrease in the rate of filtration and back washed the filter sooner to avoid the problem, which required so much pressure to clear the filter. Later in the trip, when I used the filter in "trail mode", I simply collected some clean water in my mouth and forced a bit of the water backwards through the filer and back in to the dirty water bottle. This worked easily and was a quick way for me to maintain the filter daily with little effort.

I am still very satisfied with this product and highly recommend it.

Note: Reviewer below, Herman, is absolutely correct in that my photos are not showing an optimized setup. It would increase the rate of flow if there was more tubing between the dirty bag and the filter. Also, he is correct in pointing out that there is really no way to test this system to know if it is working or not. Using this is a bit of an act of faith.

-Tony

Edited by Valshar on 07/20/2009 11:42:18 MDT.

Rating: 3 / 5

I've used this filter (this is the 0.1 micron version) in a gravity configuration with two platy bags similar to the arrangement shown a photo in one of the above reviews. I should point out that the setup in that photo is sub-optimum because the filter is mounted close to the supply bag. The water at the filter inlet would be under MUCH higher pressure and thus filter faster if the filter was placed at the other end of the tube.

OK, what's good? Lifetime warranty easy maintenance, 0.1 micron absolute (claimed) and it filters with no help from me (no pumping) so I can do something else while my water is getting filtered. It's also pretty light. My whole setup is about 8 ounces, or about half what my MSR mini-Works weighs.

What's bad? Well, the instructions say don't drop it or let it freeze. OK, I won't, but what if somebody dropped it in shipping, or knocks it off the shelf at my house or bumps it off the hanger at the shelter while I'm off taking a haircut and hangs it back up? If my mini-works filter is damaged, I can see the damage and replace the filter.

I asked Sawyer how to tell if the filter was damaged. They weren't any help. Apparently, the only way to tell is if you sicken or die and the cause is traced back to the filtered water.

The MSR hyperflow uses the same type of element, and MSR publishes an integrity test for it. So does another manufacturer who's name I'll include when I remember it. I recommend buying a filter you can test.

The bottom line is you should be careful with this filter, but even so, without an integrity test, I don't think you can ever be sure of it.

rated 3 instead of five because there is no integrity test and company's apparent lack of interest in providing one.

update: I always backflushed after a hike, but I now take the precaution of backflushing a few ounces of water after every filtering operation. My longest hike with this filter is five days. I never have experienced a significant flow reduction.

Edited by herman666 on 09/21/2009 21:05:06 MDT.