Do I have any other option for a water purifier a part from the Steripen and Sawyer models?

I came back from Costa Rica somewhat recently. CR is considered fairly safe in the health area, lot's of sites say you can drink most of the water, eat some raw foods in most places, etc.

Well, i swear i picked something up, because when i came back, after a few days of being back i started to develop increasing cramps in my stomach that would go in waves. The first day, wasn't so bad, 2nd day intensity increased, 3rd day increased some more and i started to get worried about parasites or something. Each day i had the cramps, it would go in waves, wherein for a little while wouldn't feel much and then bam cramps hit.

I went into super alkalize (lot's of green drinks, fresh lemon juice [acidic, but because of the high potassium content, quite alkalizing when digested–needs to be taken alone though]) and semi fast mode, and drank very strong antimicrobial tea (with lot's of clove and cinnamon, two of the strongest broad spectrum, plant based antimicrobials), and then would follow later on with lot's of probiotics. Thankfully, for me it cleared up pretty quick–after a couple of days of treatment following increasing symptoms over the 3 days.

Moral of the story, be on the cautious side. How that translates to water purifiers, well i personally would do a combo of Steripen and a decent carbon filter (like one of the better "straw" filters that has carbon), and of course with some pre filter first (i like linen for this use) at the very least. Hell, i so value my health and i'm paranoid enough that i might throw in a mini sawyer squeeze prefilter after the 1st prefilter if traveling all through Central or South America. Course that doesn't protect one from contamination from food or other things.

Off hand, i would say you don't need to be as cautious when in higher elevation places as a general rule of thumb, because it's usually cooler, more UV, and tends to be cleaner as a trend.

(and if i ever go back to CR, i definitely will be more cautious. I wasn't at all when i was there).

A friend tells me: never drink any water that has not been properly treated by running it through a brewery.

Words of wisdom.

Alexandra, you sure have become infamous around here, but I'll take a stab at giving you some advice.

With water purification it seems like the more you know the worse off you are.

UV and chemicals are in general, the most effective form of purification. It works on all water-borne pathogens… with the exception of large parasite eggs, like tapeworm eggs (~25 microns).

But, tapeworm eggs are not universally considered a problem. We're only concerned about them sometimes. When is sometimes? I did a little bit of searching and there's no strong consensus on when you should be concerned — besides perhaps Isle Royale NP and arctic regions where wolves may be parasite carriers.

Boiling works great. The only real downside is that the water will need to cool down, and will taste "flat." It also costs fuel, which is precious and takes up space/weight.

Filters are great, except they are prone to clogging, and don't work on viruses. Notable exception here are the better Sawyer filters, which do work on viruses.

However, Sawyer filters and other hollow fiber membrane (HFM), as well as ceramic-based filters, are susceptible to damage from freezing, which expands and cracks the filter material. Worse yet, there's no way to tell whether a filter is compromised afterwards.

Finally, no reasonable backpacking water purification system, even those with carbon cores, are effective on toxins (notably blue-green algae, agricultural chemical runoff and arsenic mining byproduct).

Personally, my thoughts:

If I planned on going on a trip that mixed urban with backcountry and potentially subfreezing temperatures I would simply take the UV for everything without power and an immersion heater for anything with. You could take a handful of chemicals as backup.

If you will be mostly without power but will have the opportunity to resupply with kerosene, white gas, or petrol, replace the plug-in immersion heater and your stove with an MSR Whisperlite International and as big a pot that won't inconvenience you. You cannot use the Whisperlite indoors, and priming it can be disconcerting for newbies to liquid fuel stoves.

My guess is that tapeworms will not a huge issue since you'll certainly be able to receive local treatment if it's a problem known amongst the locals. I don't think anybody develops resistance to parasites.

I'm very much a fan of my Sawyer as a gravity filter but it can at times be intolerably slow and does require frequent backflushing for good performance. To backflush you must take clean water into the provided syringe and squeeze it with much force into the outlet of the filter. With smaller pores the ZeroPointTwo will clog more readily and have a slower flow rate so I can't see it being an ideal option. Once you throw in the possibility of freezing into the mix the Sawyer is definitely out.

You can, of course, choose to combine filtration and UV, or filtration and chemicals, but it seems wasteful in time and weight allowances to be so cautious. However, a nice trick if you must have bulletproof purification can be to integrate the standard Sawyer into your hydration bladder and put dirty water into your bladder. Drop some chlorine dioxide inside the bladder and drink through the Sawyer for a nice lightweight solution. You can carry a second dirty bag to pre-treat with chlorine dioxide before pouring into the bladder if you need extra water capacity or to reduce wait times as well. This obviously only works when there is no chance of freezing your bladder, hose and filter. One huge downside is that it will be difficult to properly backflush your Sawyer, as you will not have stores of clean water, which becomes a bigger issue on long trips.

Hi Arla

> I had an older Steripen and experienced the battery drain during storage problem and
> it was really off-putting!
It was, wasn't it! But that has been fixed. With the first model I would isolate the batteries straight after use every time – a nuisance, but workable.

> with the new Steripen and fresh batteries, how much water can one reasonably expect
> to purify before needing new batteries?
I am going to plead ignorance here, although I am sure the info is on the web somewhere. It is quite a few litres – that much I do know. You could try the Steripen web site maybe.
The reason I don't know is because on long trips I use the high capacity Tenrod RCR123 rechargeable batteries and a small solar cell on the lid of my pack. I recharge after every use, and I don't sterilise all the water I carry anyhow. Some of the water is for cooking – that gets boiled.

> really clean water might not allow a current to pass between the electrodes and the
> unit wouldn't work
Yeah, we know about that one! Bit of a giggle.
So do Steripen, which is why they now have the Opti model. This one uses a LED instead of electrodes, so the problem has gone away completely. It's worth buying one to try it out. And Steripen are very good with support.

Cheers

I got an Opti

The Tenergy rechargeable batteries I got only worked for a few pints

Then, I got Energizer and they worked better, but still, sometimes they didn't treat as many pints as the website claimed

Maybe assume batteries will treat half as much as they claim on the website. And bring extra batteries just in case.

I got tired of it failing, so I returned it and got a Sawyer Squeeze instead.

But a lot of people are happy with it…

One problem with the Sawyer, is you're supposed to keep it from freezing, which is a problem on some of my trips.

With the Sawyer squeeze, you could bring a little bottle of high ethanol content liquid and store it in there, and have to worry less about freezing it. Even 50% vodka would be fine. If you go up higher than that, you also have the side benefit of killing many pathogens inside the filter (but you should still backflush it).

"One problem with the Sawyer, is you're supposed to keep it from freezing, which is a problem on some of my trips."

I assume my Sawyer Mini froze couple weeks ago, left it out during a night I didn't expect to get so cold. Hoping for a new and improved model before replacing it (crossing fingers they female thread both ends). The good news, is the flow rate really increased.

I would caution against this method. While it seems feasible in theory, in practice you are unlikely to clear all of the water content from the filter, potentially leaving some ice crystals to form and cause damage to the membrane. While the risk isn't extremely high, you wouldn't want to find out you damaged your filter the hard way by getting ill half way through your trip. Easier thing to do is just throw it in an interior jacket pocket, keeping it, if even a couple of degrees, above freezing and out of damage.

Stephen, regarding tapeworms: Not sure if you're aware, but it's not always simply a matter of a simple treatment like for Giardia for some species. Echinococcus granulosis (the one found on Isle Royale as well as many other places in the globe) can create cysts (each containing vast numbers of infectious "larvae") that can rupture, may have to be surgically removed, and can be life-threatening.

From Wikipedia:

"Cysts may not initially cause symptoms, in some cases for many years (Moro & Shantz 2008). Symptoms developed depend on location of the cyst, but most occur in the liver, lungs, or both (McManus et al. 2003)"

"Cystic echinococcosis is mostly found in South and Central America, Africa, the Middle East, China, Italy, Spain, Greece, Russia and the West of the United States (e.g. Arizona, New Mexico and California)."

I also found hits on a google search referring to studies done on E. granulosus in livestock in Argentina and Peru.

I personally would not use a method of water treatment that did not kill tapeworm eggs, if I were travelling in endemic areas.

If you want to get truly grossed out, you can watch a short video of some of these cysts being expelled via surgery from someone's liver at http://youtu.be/23uJnD70LNQ

Holy Larvae batman,

I've been to Spain, Greece, South and Central America, and a number of western states… I really hope i don't have that in my system!

Cameron i would still try to keep it warm and not exposed to freezing temps, but sometimes stuff happens, the alcohol would just be some extra insurance. But yeah, still keep in in an interior jacket pocket etc.

"The good news, is the flow rate really increased."

That likely indicates the filter has been damaged by freezing.

I think they said they won't do female threads on both ends because they're afraid people will use it in the wrong direction, and it isn't effective then.

Fortunately, the mini is pretty cheap.

Justin, IIRC the cysts happen in a small percentage of tapeworm infections, which is why we don't hear about them every day – but they do happen…which is obvious if you start searching YouTube (ugh – just saw a video of removal of a cranial cyst). Odds are you are hydatid cyst-free :)

As an undergrad, watching a movie of a surgical removal of a hydatid cyst nearly made me pass out in class. That experience, and the resulting awareness of hydatid cysts, is probably why I joined in on this thread despite all my vows not to…

"A friend tells me: never drink any water that has not been properly treated by running it through a brewery."

Ahem, or also winery. I'm an equal opportunity imbiber, a switch hitter, a brown man, a black man, a bronze man, a red man, and occasionally a white man.

"That likely indicates the filter has been damaged by freezing."

Yeah, I was pretty sure it was toast when I stepped over an iced over puddle not too far away on my way out of camp. It did a great job prefiltering some murky water that day, so it wasn't a total loss. Side note, I was happy that I decided not to cut the chemical backup from my pack weight… even though I forgot to use it most the time.

"I think they said they won't do female threads on both ends because they're afraid people will use it in the wrong direction, and it isn't effective then.

Hope that ain't the case.

I busted off the ends, to see if I could switch the outflow cap on a new one for the inflow on the old one… but they taper the cylinder slightly from one end to the other, so it won't work. Playing with gluing and then taping a threaded bit I cannibalized off a gravity filter hose.

Sawyer says to continue using filter for the rest of trip, if you think it might of frozen (and you have no back-up) and replace it for the next trip

I keep my filter in a plastic ziploc bag when not being used. I've seen ice crystals on the bag, but water drops on the filter itself so I should be okay

Once it was 18 F. I put filter in bag on ground in a clump of grass with stuff on top. No sign of freezing.

Since sickness from water is probablistic, that is, you probably won't get sick if you do it once, but if you routinely drink untreated water, you'll probably eventually get sick, maybe you don't need a back-up. In the un-likely event your filter freezes, for the rest of the trip drink untreated water. Probably won't get sick.

I still have to read the all thing, so forgive me if this question is slightly unrelated or has already been answered. I kind have to go to an internet point every time I want to go on-line..

Can I use a coffee filter as a pre-filter, along with the Steripen and will it work ok with water bottles/hydration reservoirs and pan/pots or would I need some sort of adapter for it?

Could I just make this system my Water filter/purifier of choice?

Cheers.

yes…

You do not actually *NEED* to filter with the steripen. Filtering is only needed to remove big things that gross you out.

If the UV can't penetrate cloudy water, it won't work right. Things like cholera hide on large particles. A pre filter is a good idea in those conditions.

SODIS with a pop bottle is the poor person's steripen.
Settling and filtering through 2 layers of Sari cloth is the poor persons pre filter.

http://www.sodis.ch/methode/index_EN

http://en.wikipedia.org/wiki/Cloth_filter

> Can I use a coffee filter as a pre-filter, along with the Steripen
Absolutely! Good combo.

> will it work ok with water bottles/hydration reservoirs and pan/pots or would I need some sort of adapter for it?
Yeah, well, that gets a bit more tricky. You have to support the filter paper. That's where one can go MYOG, or buy a GSI coffee filter maybe.

Cheers

A guy I've hiked with has an actual metal coffee filter that screws onto a nalegene bottle. Works pretty well.

The Rapid Pure filter makes claims about being good for viruses. You could make a gravity system with it.

http://www.rapidpure.net/

http://www.gofastandlight.com/Best-Hydration-Pack-Water-Filter-Viruses-Flows-Fast/productinfo/W-R-MINI/

"The Rapid Pure filter makes claims about being good for viruses. You could make a gravity system with it.

http://www.rapidpure.net/

http://www.gofastandlight.com/Best-Hydration-Pack-Water-Filter-Viruses-Flows-Fast/productinfo/W-R-MINI/"

I call scam. From the second link:

"Untreated source water can be poured into the hydration bladder and drawn through filter with just a 2 PSI suction. Competitive filters can require a 10 to 20 PSI draw."

2 PSI is an absolute enormous amount of suction to produce yourself. Equivalent to drinking through a vertical 4'6" straw. Try it sometime.

20 PSI draw is literally impossible in any normal environment.

I could be wrong. Maybe the 2 PSI and 10-20 PSI were put in there by an incompetent "tech" author. They could have been given inches of water and not known the difference. Here is the paper that RapidPure claims as evidence of its stated virus removal efficiency.

http://aem.asm.org/content/77/10/3500.full

I am not sure that it can be called a scam. They very explicitely claim they meet EPA requirements, and their office is in America (Lakeland, MN). You don't make that sort of claim without good evidence to back you up: the EPA is known to prosecute quite vigorously. I know some guys went to jail.

Interesting.
Chers