Sawyer Gravity Filter

Hi Eric (Lundquist),

I'm using the exact setup as you, but I haven't cut the bottom (well, top in gravity mode I guess?) of my "dirty" Platy, yet. I've thought about doing it since it would obviously speed up water retrieval duty, but I'm hesitant because I don't want to take away the option to carry an extra 2-liters of water with the dirty Platy if the situation arose (e.g. long dry stretch). Although…

The other possible positive aspect to your setup that could sway my scalpel is the elimination of back pressure on the dirty container. It seems like I have to burp the clean container a bit when filtering in gravity setup and I wonder if this would eliminate that problem? Any insight to this? Thanks.

Alex,

I've found that if you eliminate any extra air from the "dirty" and "clean" bladders you won't have to burp them in the middle of filtering. I did consider not cutting the bottom of the bladder for the exact reasons you mentioned. One alternative was to purchase the Zip variety of platypus but they weigh a lot more than the standard 2L bladder that I am using. I would rather carry (x2) 2L bladders with one cut out bottom for the times when I'll see a dry stretch. I've also found that it is easier to scoup the water with the bottom removed than it would be to try and submerge the standard opening.

Eric, Thanks for the insightful reply. It sounds like we've gone through the same thought process. I checked out the Platypus Zip style bladders too and decided against them due to the weight and possible failure.

Good to know about removing the extra air from the setup. It makes complete sense and now I'm wondering why I didn't try this before. I guess I'm pretty lazy with this setup and just hang and forget rather sloppy. Well, that's the beauty to the gravity filter anyways, right?

Okay, I'm going to go ahead and cut out the bottome when I get home tonight. I have an older Platy that has a pretty severe crease in the bottom that I don't trust anyways. Thanks again for helping me think this through.

Ok, so I'm going to bump this thread back up because I'd like some more information. I've looked at the website and need a bit more info. I'm not actually a backpacker but instead a bikepacker. I'm pretty positive there are quite a few other bikepackers on this board as well.

I carry my water bladder in my frame bag. I'm currently using a 3 liter Camelback bladder with a quick disconnect so I can easily pull the bladder out of the pack and attach it to my MSR pump. I feed the hose through a port and attach it to my handlebars for easy drinking.

I'd like to use a different filter as I feel like it's a pain in the butt to filter the water with the pump. My weak and scrawny arms get tired. That being said, I've used pills/steri-pen/pumps and have had Giardia from one of those. The pump is a "safe" thing for me so I've dealt with the bulk and weight. On top of that, I need water "right now" so I don't want to wait for pills/drops.

All that being said, looking at the Geigerrig website, I'm not exactly sure what all I need. This is what I what:

A bladder: What is the difference in the WIDTH between the 3 and 2 liter? I'm leaning more towards the 2 liter.

A filter

Tubing/bite valve/quick realease

I don't really think I need the pump or whatever it is that forces water through. I have no problem sucking water from a valve and I don't think I'd have the space for it anyway.

That's a pic of what I'm currently doing (this is not my actual bag just a pic that is using basically the same set-up).

Thanks for any insight you could give me.

Travis….May I suggest you contact Bob Geiger at the information below with your questions as I am sure he will answer all your questions as he did mine.

Bob Geiger
801-823-3336
bob@hubcityoutdoor.com

I just picked up one of these: CamelBack Fresh Reservoir Filter

I figured I’d try it as a new, lighter inline carbon filter for my gravity filter system. It’s quite a bit smaller and lighter (~1.3 oz vs 3.3 oz) than the Katadyn Carbon Filter.

It requires the quick connect couplings (like the sawyer filter) in order to install it. This is actually kind of a nice thing because it means it’s easier for me to remove it from my inline filter when I don’t need it.

I’ve played around with it a little and it definitely does not seem to affect flow rates, nor does it gain a bunch of weight after it gets wet. Nice.

It’s supposed to be good for about 120L before the carbon catridge needs to be replaced. Replacement cartridges are $20 for 2.

Nicholas — what filter do you pair the Camelbak carbon filter with?

Hey Ben,

I'm using the Sawyer 0.1 micron filter as my primary filter. I pre-filter with a cut down 1-micron bio diesel filter bag if the water isn't clear.

– Nick

NIcholas,
I just got the Sawyer, and it filters really really fast with tapwater. I know its going to be slower with dirty water, but whats the flow rate you average in the field?

I made a homemade gravity filter, the equivalent of the ULA Amigo Pro but an ounce lighter, with a Katadyn Hiker Pro replacement filter with the excess housing trimmed off.

I thought I would save weight using the Sawyer Inline filter. However, I found that with the necessary connector added at each end, it weighs 3.0 oz., 0.1 oz. more than the cut-down Katadyn Hiker Pro (2.9 oz.). In other words, the Sawyer is going back.

Mary, I did something like you with the Katydyn filter, but I switched to the Sawyer for longer life, better filtering, and lower weight. Total filter systems and connections will affect the filter weight differently, but as for the filters themselves, my Katadyn filter weighs almost 3/4 ounce heavier when wet then the Sawyer. Since filters don't really dry out in the field, I use the "wet" weight.

The Katadyn gravity setup isn't as easily backflushed, unless I'm mistaken.

Since I integrate my hydration tube into the filter system (I don't carry an extra tube), the Sawyer still came out to a lower weight for me.

Hey Travis,

For the most part, I've found the flow rates to be pretty good in the field with the sawyer, say around 2.5 min/liter range. I'd say that's about the same or just a little slower than what I get with tap water at home. I have to condition this statement with the aknowledgement that I tend to find and filter pretty clear water sources to begin with and/or pre-filter, so this helps to keep things filtering quickly.

If you don't pre-filter or you have really turbid water, you will notice a definite degradation in the filter's performance over time. On my last overnighter, we got a bit of rain/hail/snow and the creek was running super muddy. For some reason, I wasn't thinking and filtered the water through the sawyer without pre-filtering first. It worked fine for the first two liters but when I went to filter more the next morning, it ended up being pretty clogged and slowed down to an agonizing trickle, probably on track for a 10-15 min/liter pace! Needless to say, I canned it and used some back-up chemical treatment for the walk out since I couldn't seem to sufficiently backflush it in the field. I had to do some serious backflushing at home to return the filter to its peak performance, but now it seems to be back to normal.

THREAD DRIFT WARNING…Just a FYI Travis, I posted a couple of pics of my trailstar with the pentanet 2 under it recently. Not sure if you saw those, but I think you had told me you were interested in that combo.

Cheers,

Nick

Thanks Nicholas. I'll be sure to check out that Trailstar thread!

> I had to do some serious backflushing at home to return the filter to its peak performance,
> but now it seems to be back to normal.

Now that IS interesting, that backflushing did work.

Cheers

I just picked up the Geigerrig at a Costco warehouse in American Fork, Utah. I weighed it on a triple beam balance. The bag is 96g, the pump and hose is 84g, the drink tube is 58g, and the inline filter with the connectors as shown earlier by Bob, is 46g. They were selling the hydration bladder at a 40% discount and the inline filter for $22.99.

I think it looks very interesting.