Platypus gravity water filter

Posted by: ABcowgrl

Platypus gravity water filter - 06/09/12 08:28 AM

Has anybody used the platypus gravity water filter? Was considering purchasing one as my water treatement system.I hike the canadian rockies so glacier silt will be a filter issue.Any suggestions on something better?
Posted by: lori

Re: Platypus gravity water filter - 06/09/12 09:59 AM

For heavily silted water, an additional stage of settling out debris is needed for any filter. In some places a flocculant can be needed to more actively removed the particles.

Pre-filters can be helpful but can also clog if the water's too silty.

I use a Cleanstream but have not gone anywhere that the water had a lot of silt and debris in it. All commercial filters are going to be about the same in terms of filtration; what differs is how they work - some people prefer pump filters, some like the gravity filters. I have a Hiker Pro and a gravity filter, and prefer the gravity filter because it is lighter and multi-use (it can also be a shower or water bucket, useful for carrying water to drown a fire).
Posted by: OregonMouse

Re: Platypus gravity water filter - 06/09/12 02:48 PM

I know that our longtime member phat, who also is in Alberta, uses chlorine dioxide (Aquamira or Katadyn MicroPur in the US; I've forgotten the Canadian brand name) to avoid the filter clogging problem. IMHO, you still want to get some of that silt out--I wouldn't want it scouring my insides!
Posted by: ABcowgrl

Re: Platypus gravity water filter - 06/10/12 12:02 AM

Just saw the first platypus filter system on display today.They're supposed to have a silt filter as well,but didn't have too much time to really investigate it further.I've previously just done the coffee filter after letting water settle and then CD tabs.I'm mostly worried about how dependable the filter is on this model...pretty slim,might have some serious clogging problems with glacier run-off even with using settling/coffee filter??? Not sure.
Posted by: lori

Re: Platypus gravity water filter - 06/10/12 12:41 AM

I don't think you're going to find a filter that would not have clogging problems if there's a lot of silt.

All these filters you'll find for backpacking are designed to address protozoa and bacteria, not silt. Even the ones with pre-filters are going to be falling short with really silty water.
Posted by: aimless

Re: Platypus gravity water filter - 06/10/12 02:55 PM

Cloudy water full of 'glacier milk' is sheer hell on water filters. The particles are so fine that no filter can handle them without massive clogging. frown

You can experiment with settling, prefiltering and flocculents, but in the end, if you're going to be drawing out of a milky stream, I'd go with chlorine dioxide tablets and save the filter for use only with clear runoff sources.
Posted by: phat

Re: Platypus gravity water filter - 06/10/12 02:57 PM

Originally Posted By OregonMouse
I know that our longtime member phat, who also is in Alberta, uses chlorine dioxide (Aquamira or Katadyn MicroPur in the US; I've forgotten the Canadian brand name) to avoid the filter clogging problem. IMHO, you still want to get some of that silt out--I wouldn't want it scouring my insides!



Yes indeed. the canadian brand name is "Pristine" - it's the same thing as Aquamira - chlorine dioxide. Works fast (on anything you're gonna find in the canadian rockies) and is impervious to silt.

I've drunk lots of glacial silty water. if it's *really* silty it's nasty, but by "really silty" that's usually the stuff that's literally meters from the feet of the glacier. So for example here:



I didn't take that water - instead I just hiked up to the glacier and collected some melting off the top (instead of coming out of the bottom) of the glacier).

Now, having said that most of the time, I have no problem at all. The "normally" silty water, I have no problem drinking, but the thing to remember is that this is often very finely ground up limestone - it won't hurt you, but it can put some people's digestive systems out of whack, so you get the poops (and think you've had bad water..) Generally I've found if it doesn't taste funny (like it has ground up chalk in it) it's fine and doesn't bug me. the water at the base of that glacier above did, OTOH, the water in the pics below was all fine for me:






And for the record, the water in the *first* picture above clogged three filters in four point campground, who all ended up "yogi-ing" a dose of pristine from me so they'd have water wink

the other thing to remember is it's usually not hard to find "less silty" water when the big creeks are running hard - just look for a little side feeder or spring or seep.
Posted by: Robotmoose

Re: Platypus gravity water filter - 05/07/13 03:56 AM

Reviving a dead thread, but I've recently purchased one. Or, more accurately, traded in my MSR Miniworks for it, the decision was born mostly out of laziness.

I picked up the "Bottle" system, because it was reasonably sized, a little cheaper and (most importantly) was designed to mate onto Cascade (MSR, Nalgene) water bottles. I use MSR dromedary bags, so this was a mandatory choice for me.

I'm happy with it, I think the bottle system is the most practical for my standpoint and use. I did modify it by splicing in a camelback quick-connect unit to accommodate my homebrew hydration system - now I can fill it without taking it out of my backpack. +1 for laziness.

FWIW chemical treatment is less of an option for me, I will resort to it if needed, but I've lived on well water for my whole life, and I just can't stomach the city water/municipal pool taste the chemical treatments produce, so mechanical filtration it is.
I agree that in a glacier-dense area, chemical treatment or boiling may be the only options.