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How often is it necessary to backflush the mini? Do you backflush before or after your trip? Do you bring the syringe if only out for a couple days?
I would say it depends on where you use it and how much you use it. If I knew I'd just filtered five gallons of questionable, algae-laden, scum-filled puddle water, I'd be flushing. But in the sierras (where I mostly hike) I'd wait until the filter seemed a little slower than it used to/is supposed to. For me, with the bigger sawyer, this took about 4 to 6 two-night trips IIRC. I am guessing that the mini clogs earlier, but honestly, I don't have a scientific point of reference to back this up. Just more water going through fewer pores in a smaller space. Oh, well maybe I do. Someone else please . . .
People have reported problems with Sawyer filters clogging, like mineral deposits in pores.
Maybe best to flush before and after each trip. Before trip filter a little water to make sure it's working.
I should add, when they get a little clogged they work the same but at a slower rate. If used as a gravity filter, this won't matter as much as when you are hoping to filter as you drink through a small, soft container like a 1 liter smart water bottle or the stock Sawyer bag.
With a hard sided bottle you can apply more pressure, so if the filter is a little clogged it's not as bad
With a collapsible bag, they are inherently weak with the welded seams and the sides of the bag welded to the screw top, so you can't put so much pressure on it or it will break? So it's a little more sensitive to partially clogged filter?
Thanks for the info. Theres got to be a way to backflush this thing with an item you already bring or something smaller/lighter than the syringe
If I'm out for anything more than 5 days, I bring the syringe. Shorter trips don't pose much of a problem, although filtering on the last day can be a little slow. I use 1L smartwater bottles, so I don't have to worry about bursting a bag.
I bought a smaller 30ml syringe to make it more compact and it saves a tiny bit of weight.
Someone should come up with an in line pre-filter for chunky water. MSR uses a bit of sponge in the intake hose for a pre-filter. It would be easy to cut a chunk to fit into the neck of the dirty water bottle. That would be light and cheap and easy DIY.
It takes more time, but you can still do the bandana or coffee filter trick using your cook pot. Allowing silt to settle can help too.
Too bad the threads don't allow screwing soda bottle onto output. You can exert a fair amount of pressure, maybe good enough to backflush.
You can buy the in line adapter kit for the Squeeze. Add a little chunk of hose and you can adapt all kinds of bages and bottles to the mini.
Great idea. There's a little $12 inline filter that I think goes with the Platy gravity set – it's for removing taste not microbes, but it will likely work well to spare the filter. Then when the pre gets clogged just switch to filter only. Another option would be to put a fine mesh screen inside the top of your bottle or bag to spare the filter a bit. I might have to hit the hardware store.
This should get the chunkies. Easy to clean or replace. A real boat anchor at 0.5g :)
I was considering going with a smaller syringe, but read this interesting post:
I guess in a pinch and the filter was completely not working, it would do.
I felt okay about the 30ml syringe, but it wouldn't be practical to go much smaller. I think the way to go for general maintenance is to rig up something that you can hook to a faucet to backflush with. It's good to know about the channeling issue; I wouldn't sweat if for a once-in-a-blue-moon backflush, but relying on a small syringe over a season or a through hike looks like a bad idea.
The Luer Lock tips on the syringes are the weak link in the Sawyer system, IMHO. It's a handful to get the thing pressed tight to the nipple on the filter and pushing in the plunger on the syringe– not impossible, just a bit clumsy and weak. With a little 10ml syringe, you wouldn't get much done.
Here's the 30ml (marked 35ml) next to the Sawyer supplied 60ml unit. It is 0.6oz with packaging vs the Sawyer at 1.2oz, so the saving in space and weight is minimal. For a day hike or overnight you could just carry MicroPur tablets as a backup. Back-flushing at home after each trip makes sense, much like putting fresh batteries in your headlamp.
It's Dale, Ted ;)
eBay. I got three for $6 and change including shipping. I imagine some medical supply or pharmacy would have something. Search on "30ml Luer lock". After reading about the channeling issues, I would tread cautiously: saving 0.6oz and having a dead filter doesn't compute.
Sorry Dale, I had just email a guy at work named Dave 4 times. The brain knew that it was you; I guess muscle memory at my age is a little harder to correct.
Thanks for the info.I'm sure you've been called Ted at least as many times as I've been called Dave.
It's okay man, Dave's not here…..
When I do that bit at work no one knows what I talking about! ;^)
BTW, has anyone heard/read anything from saywer stating that using a small syringe to backflush is a bad idea. I have a really small one that I was going to carry to backflush in the field if it every becomes necessary (it hasn't yet).
Scanned from the instruction card packed with the mini:
The idea is that a weak backflush will only clean the path of least resistance and each time you try to clean it, only those areas you cleaned with the low pressure stream will flow or be cleaned in successive attempts. That will create channels of clear tubes in the filter media with others permanently clogged. Time will tell!
As to "Dave's not here", I wouldn't expect anyone under 50 to have a clue. It came out in 1971, at the "height" of my "high" school experience (http://en.wikipedia.org/wiki/Cheech_and_Chong_%28album%29)
Dave's not here, man!" – by Cheech and Chong
(Soft knocks at the door)
CHONG: Who is it?
CHEECH: It's me, Dave. Open up, man, I got the stuff.
(More knocks)
CHONG: Who is it?
CHEECH: It's me, Dave, man. Open up, I got the stuff.
CHONG: Who?
CHEECH: It's, Dave, man. Open up, I think the cops saw me come in here.
(More knocks)
CHONG: Who is it?
CHEECH: It's, Dave, man. Will you open up, I got the stuff with me.
CHONG: Who?
CHEECH: Dave, man. Open up.
CHONG: Dave?
CHEECH: Yeah, Dave. C'mon, man, open up, I think the cops saw me.
CHONG: Dave's not here.
CHEECH: No, man, I'm Dave, man.
(Sharp knocks at the door)
CHEECH: Hey, c'mon, man.
CHONG: Who is it?
CHEECH: It's Dave, man. Will you open up? I got the stuff with me.
CHONG: Who?
CHEECH: Dave, man. Open up.
CHONG: Dave?
CHEECH: Yeah, Dave.
CHONG: Dave's not here.
CHEECH: What the h***? No, man, I am Dave, man. Will you…
(More knocks)
CHEECH: C'mon! Open up the door, will you? I got the stuff with me, I think the cops
saw me.
CHONG: Who is it?
CHEECH: Oh, what the h*** is it…c'mon. Open up the door! It's Dave!
CHONG: Who?
CHEECH: Dave! D-A-V-E! Will you open up the g***** door!
CHONG: Dave?
CHEECH: Yeah, Dave!
CHONG: Dave?
CHEECH: Right, man. Dave. Now will you open up the door?
CHONG: Dave's not here.But most everyone st work is my age (I'm 53). I understand the 30 something not getting it, but everyone else… At least someone here does! :^)
For a pre-filter I cut a circle of gold coffee filter and slipped it under the washer on the intake side of the filter. Effectively weightless.
I've found the best solution to be to use an adapter like the previous pic (couple bucks on amazon) that you connect to the output nipple via the included "straw" to a bottle. It's also the easiest way to fill up IMO. Since it is already attached after filling simply remove the dirty bag/bottle and squeeze back through some of the just filtered water. The "staw" fits so tightly that with a plastic bottle you can get really good pressure through it. I do this every time and have never had any slow down on the flow. It's definitely suffice for maintaining good flow on an extended trips. I still use the syringe when I get home but I honestly don't think I've ever needed to. P.S. The straw can be cut down significantly if you prefer. I just like to keep it long in case I need to use it as intended.
I haven't been using the Mini as long as I did the Squeeze, but I have used the Squeeze on a 7 day hike and it never needed any sort of backflush while on the trail. Depending on the expected water sources, I personally would be fine going the same length of time using the Mini without backflushing…
I always backflush the filter when I get back from any hike though. I fill a large glass with water and add some bleach to it, then backflush about 6 – 8 syringes through the filter. Then I let the filter sit for about an hour, and then I just flick the filter to remove most of the retained water. Then I put it up for storage.
Before heading out on any trip, I always fill a bladder with some water and "test" the filter before leaving. This lets me know that the filter is in working order before I head out, and it also flushes any of the bleach water back out of the filter. On the trail though, I still waste a little from the first filter before filling any water bottles.
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