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  • #1654175
    Heath Pitts
    BPL Member

    @heathpitts

    Locale: Nashville

    I bought some granulated aquarium charcoal from a local aquarium store. I didn't know about the powdered type.

    #1654329
    Brad Groves
    BPL Member

    @4quietwoods

    Locale: Michigan

    The Sawyer filter is super easy to use, and the recent update w/incorporated quick connects is nice. I don't bother with a water bag. I just spliced the Sawyer into a 3L Platy hoser bladder; I did add a silt stopper in line, added a hair under an ounce. Point is, I have a 3-ounce water filter that requires nothing special and that takes out everything I'm concerned about CONUS.

    I use the hydration bladder as my water source. Go to the stream/lake/whatever, submerge and fill, screw on the hydration hose w/inline filter. Toss the bladder in my pack, drink filtered water as I go. If a buddy needs some filtered water, just hang the thing from a tree limb and gravity feed. No fuss.

    #1654377
    Phil O’Connor
    Member

    @philoconnor

    Locale: Oh ya know

    Brad, you think you can post some pictures and maybe some quick info on the pieces needed to achieve the no fuss clean water system NFCWS

    #1654822
    Brad Groves
    BPL Member

    @4quietwoods

    Locale: Michigan

    Hey Phil, I don't have pics of the system. Really straight-forward, though. A Platypus 3.0L Hoser; cut the hose ~midway, splice in the Sweetwater SiltStopper; cut the hose a couple inches further toward bite valve and splice in Sawyer SP-122 (comes w/quick connect fittings). That's all.

    The Sawyer product pics show the filter spliced into a hydration pack; it's literally as simple as cutting the tubing and shoving the tubing on the fittings…

    #1654937
    Jeffs Eleven
    BPL Member

    @woodenwizard

    Locale: NePo

    Brad,

    Do you think a carbon accessory (Katy) added to this setup would decrease the pressure so that it would be really slow?

    I have been thinking about this setup but with the carbon element. Whaddya think??

    #1654960
    Brad Groves
    BPL Member

    @4quietwoods

    Locale: Michigan

    Jeff, I don't think it would slow the flow significantly. It would add (assuming the Katadyn bottle adaptor w/carbon) a little over 2 more ounces to the filter system, which I'm guessin you know. I don't remember there being a nub on the bottom of the carbon to push on a bite valve, but if you were just gravity filtering that'd be fine.

    If you're gravity feeding that way, I'd assume the additional weight of another bladder to drain into, as well… not a big deal, really, but adds another couple ounces to the system. For most backcountry travel I personally haven't found the need for a carbon treatment… way back, I'm not concerned about industrial heavy metals or flushed Rx meds in the water… and if the water tastes a little funky, it's a pretty sure bet it won't taste as bad as iodine treatments would, so I take it in and wonder about it as part of the "local culture."

    Hang it high as you can for gravity feed. I can almost always find something at upper arms reach, but you could also toss a line over a low limb. W/longer hose, filter more toward bottom, get more head/pressure that way.For drinking as you go, by keeping the bladder on top of my pack (ie under lid/top strap) I've found that it flows well and is easier to load/unload the pack.

    #1654974
    Jeffs Eleven
    BPL Member

    @woodenwizard

    Locale: NePo

    Thanks for the info…

    Yeah I guess it'd be kinda pointless. The water here is pretty good anyway…

    The carbon stoptop does have a nipple on the bottom but I guess its not really needed so close to the source. (water source)

    Thanks

    its easy to add too many things to a project to make it perfect- usually makes it 'too perfect' and it fails

    #1655245
    Matt DeWitt
    Member

    @tritan

    Locale: Midwest

    would love to see pics of this system

    #1655929
    Brad Groves
    BPL Member

    @4quietwoods

    Locale: Michigan

    I'm not sure how much this could help, it's a hose w/an inline filter, but…

    filter

    Mine usually gets tossed sideways under the top lid or strap, hangs from the loop on bladder for gravity. The placement of the filter is not great for using a drop-in hydation sleeve; the filter's a little too close to the bite valve to get the bite valve out far enough.

    #1656744
    Gary Dunckel
    BPL Member

    @zia-grill-guy

    Locale: Boulder

    Heath, have you tested your aquarium charcoal setup yet? I followed your idea, and so far I'm not sure that I'm impressed with my results. Here is my own test:

    Since my main interest is to remove the chlorine taste of AM or tablets, I first filled a 2-L Platy with tap water, then added the pills, waited 15-20 minutes to let them fully dissolve, and then I ran the water through the various filter modes:

    (1) 0.1 micron Sawyer filter with 2' of tubing from the Platy, no Siltstopper/charcoal. I collected 8 oz. of this water in a glass.

    (2) Sawyer with same hoses, but with the Siltstopper (filled with charcoal, and a custom steel screen to keep the pellets from escaping through the tube hole) placed just above the Sawyer .1 micron filter. I ran maybe 8 oz. of water through the system before collecting my 8 oz. sample, hoping to purge the filter and Siltstopper from step (1).

    (3) As a control, I then attached a Frontier Pro filter, ran maybe 8 oz through to fully wet the day filter. Then I collected another 8 oz. sample.

    (4) I dissolved one Micropur tablet into a 1-L Platy, to act as another control, for unfiltered water.

    My findings:

    The treated water that was not run through a filter came out as you would expect–a mild taste of chlorine and the usual white floaties from the pill.

    The water the Frontier Pro provided tasted just like my tap water (I'm on a well, with no chemicals involved–very pure artesian water). The FP seemed to remove all traces of the chloride from the pills.

    I really couldn't taste a difference between the 2 Sawyer samples. Both had a slight taste of chlorine. I'm thinking that the granule size of the aquarium charcoal is too large to have much of an effect (they're little cylinders, 2.0 mm x 4.0 mm). I think I'll put some charcoal pellets into my coffee grinder and see if I can reduce the size. I'll toss any powder, as I think that might clog up the system somewhat. Then I'll repeat my test, and see if smaller bits of charcoal make a difference.

    I'm desperate to learn from others how their results turned out. I'm also tempted to break open a spare FP to learn what size charcoal pieces they are using. Seems like I'm totally missing something here.

    #1656746
    Bob Gross
    BPL Member

    @b-g-2-2

    Locale: Silicon Valley

    "Seems like I'm totally missing something here."

    Do you understand the difference between charcoal and activated charcoal?

    –B.G.–

    #1656747
    Heath Pitts
    BPL Member

    @heathpitts

    Locale: Nashville

    I haven't been able to test it in the field yet. But that is a good point on the granule size. Please update us if you find something that would work better. Maybe purchasing the charcoal refills for the katadyn carbon adapter would be the better setup

    #1656761
    Brad Groves
    BPL Member

    @4quietwoods

    Locale: Michigan

    Gary, carbon filter elements are "solid," not pieces/powder. A tube of carbon, if you will…

    #1656765
    Gary Dunckel
    BPL Member

    @zia-grill-guy

    Locale: Boulder

    I think I do, Bob, pretty much. Do you suppose that the aquarium charcoal I bought isn't actually the activated type? That doesn't make sense. But it's looking like water filters tend to use a granule on the order of 14-30 sieve size. The stuff I bought is 8-10 (larger). I'll try the coffee grinder next.

    #1656766
    Jeffs Eleven
    BPL Member

    @woodenwizard

    Locale: NePo

    Hey, Brad …with gravity you gettin bout 1L/ min?

    I think your setup is money. (having never used it) If it'll get at least a liter a min its probably bout as good as can get. (I guess you could always go cuben bag)

    #1656767
    Gary Dunckel
    BPL Member

    @zia-grill-guy

    Locale: Boulder

    I'm not sure what you mean, Brad–a tube of carbon? Is it a solid, but porous, block of material that the water sneaks its way through? I see where several supply houses do sell activated charcoal in varying particle sizes for all sorts of applications–aquariums, water filters, kidney dialysis, etc. I'd think that the higher the total surface area, the more effective the result. But a fine powder would be tough to contain in the housing, I would think. In the case of the SiltStopper, I think a powder would find its way around the filter thing and pass right on through.

    I appreciate everyone's help here.

    #1656769
    Brad Groves
    BPL Member

    @4quietwoods

    Locale: Michigan

    "solid, but porous, block of material"

    yup. to tell you the truth, I'm not 100% sure that's the way the FP is set up, but it's my recollection. I know the Hiker/MW/etc use the carbon core. No arguments about your varied finds, just trying to describe the system in question.

    Jeff, yeah, I get a liter a minute. Fresh, sometimes it seems even a little faster. After filtering for two for close to a week the flow drops off; it's pretty easy to rig a field back-flush system if you plan on doing longer trips. (just another hydration hose w/quick connect)

    #1656790
    Michael Davis
    Member

    @mad777

    Locale: South Florida

    I have a different approach to charcoal. I went to an aquarium supply store and bought a jar of granulated charcoal, rinsed off about an ounce of it. Them I made a tiny little bag from noseeum mesh about 2 inches long by 1 inch round, filled it with the 1 ounce of charcoal and sewed up the opening. I simply drop that bag of charcoal in my drinking bottle.

    For a filter, I use a Sawyer gravity filter (the old Amigo Pro).

    #1657442
    Greg Mihalik
    Spectator

    @greg23

    Locale: Colorado

    Brad –
    You posted this shot earlier:
    SiltStopper

    I looked many places on how to connect the SiltStopper, and found only one reference, on REI, that states "Attach the SiltStopper such that the Red side filters the Incoming water". Seemed a simple question until I started looking.

    I have to believe that direction makes a difference. You'd think MSR would mention it on their packaging….

    Do you have source that says the opposite?

    Thanks.

    Edit: A reply from Cascade/MSR says that the filter can be used in Either direction.

    #1657449
    tkkn c
    BPL Member

    @tkknc

    Locale: Desert Rat in the Southwest

    The directions do say put the red side on the source. If you are using carbon in the filter, then you have to put the clear on the source, or all the carbon will get flushed out of the prefilter.

    #1657453
    Greg Mihalik
    Spectator

    @greg23

    Locale: Colorado

    No instructions on the freestanding SiltStopper bubble pack….

    The assumption is the direction does Not make a difference?
    For instance the filter doesn't have a radial gradient?

    Regarding carbon –

    The Katadyn charcoal filter uses about 25 grams, for about 50 gallons of filtration.

    I can get about 5 grams into the Siltstopper, implying about 10 gallons of filtration. Is that even worth the effort? Or does that 5 grams in a Siltstopper go a lot farther than 10 gallons?

    Obviously in clear water it will last long time, but in that case, why bother with carbon at all?

    Edit: I added a screen to the output end that keeps the carbon in place.

    #1657465
    Gary Dunckel
    BPL Member

    @zia-grill-guy

    Locale: Boulder

    Greg, I'm having the same dilemma as you. I picked up a SiltStopper during REI's recent sale, and I went to work on activated charcoal. First I tried some cheap aquarium charcoal, which I ground down to 1.0-1.5 mm pieces in my food processor. I put 3 Micropur tabs in my 2-liter Platy dirty bag (extra, to ensure a significant chlorine taste). I tasted the water first (much chlorine taste, of course), then I ran the water through the SiltStopper and collected a sample. Still a serious chlorine taste. Then I added my Sawyer filter below the SiltStopper, let a cup flow to wet/purge the filter, then collected another sample. Still a strong chlorine taste. I then replaced the entire system and connected a Frontier Pro, with no SiltStopper. The sample I sipped tasted chlorine free!

    Later, thinking the lack of good results might have related to the quality of the charcoal, I picked up a "special" and expensive aquarium charcoal concoction called Chem-Pure Elite, which also has some type of ionized beads that purportedly adsorb certain metals (maybe good if collecting water near our CO mines…). I then ran an identical set of tests as mentioned above. Same exact results!

    I've sent an e-mail to Chem-Pure to see what they think about using their products in a gravity filtration system, and will hopefully learn something this week. This morning, I also sent an inquiry to Cascade Designs. I asked them which end of the SiltStopper to connect to the dirty bag, and I also asked their opinion regarding our activated charcoal trick (and if they thought of selling little mesh bags of charcoal to add to the SiltStopper).

    So I'm getting fairly frustrated about this whole concept that we've been playing around with. I'm thinking that if I'm going to use AM or tablets, then I'll stick with my Frontier Pro. If I'm not worried about viruses, I'll use my Sawyer 0.1 micron filter, forgoing chemicals. Either way, I'll keep using my Coghlan's yellow filter funnel for ease of filling my Platy streamside (it also gets the bigger floaties). Hopefully, backflushing the Sawyer will remove that red dust from the Aspen area streams. I'll consider the FP disposable. Maybe Katadyn's carbon filter is the only answer to removing the chlorine taste (assuming that it really does…has anyone tried it?). But at 3+ oz, it's not too appealing to me.

    I'll post again when I hear back from Cascade Designs, and also Chem-Pure. If anyone has a better experience than mine, I'd love to hear about it.

    #1657467
    Heath Pitts
    BPL Member

    @heathpitts

    Locale: Nashville

    I'm interested to see what you guys come up with on this. I originally just added the carbon as an afterthought to the siltstopper. I never really thought about it not working at all though. I figured that I would need to replace the carbon after each weekend trip. Maybe there is a better carbon solution out there

    #1657500
    Greg Mihalik
    Spectator

    @greg23

    Locale: Colorado

    On a Frontier Pro –
    Is there a way to attach typical hydration tubing to each end?

    Maybe this could follow a Sawyer Filter to provide activated carbon water clarification. Although rated for only 50 gallons, Aquamira states this is about half the expected thruput, and as a post-filter perhaps it would do even better.

    Edit: The answer is Yes. I found the Jason Klass video associated with Frontier Pro for sale in the BPL store. He shows it there.

    #1657584
    Gary Dunckel
    BPL Member

    @zia-grill-guy

    Locale: Boulder

    Good idea, Greg. It would be nice to break open a FP and see how it's made. If there are two different components–a filter, and a carbon setup–maybe there's a way to get rid of the redundant filter element somehow, to lighten it a bit and also improve flow rate. The cotton pre-filter thing could be removed as well. Whoever has the first spent FP needs to perform an autopsy on it and report back to the group. I can't find a way to open one up, and to do so forcefully would preclude getting it back together so it would function. At any rate, I'm betting that a clogged-up filter would still have some good charcoal life remaining, providing that it was used with water sources fairly free of the inorganic stuff that carbon adsorbs. But the better way is to use a new FP. The flow rate would probably remain good for the life of the activated charcoal. But we're adding 2 oz. to our gravity filtration system by adding the FP. I guess the good thing is that we would have a redundant filter in case the Sawyer fails. This might be OK for a group outing, but for my solo trips I'd rather keep things simpler and lighter.

    Geeks R Us, so let's keep thinking on this…

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