Pamela:

Aqua Mira, Klearwater and Micropur are all the same chlorine dioxide. Aqua Mira requires a 5 minute pre-mixing time. After that, all three have the same "treatment time" -- 15 minutes or so to kill the really small stuff like bacteria and viruses -- longer time in colder water.

However, when it comes to the bigger stuff like cysts -- esp. organisms with a protective shell like cryptosporidia -- treatment time shoots up to 4 hours! Again, this is the same for all three.

To me, a four-hour treatment time is of dubious value -- but I suppose it's theoretically better than using chlorine or iodine, which are both ineffective against crypto, regardless of the length of treatment time.

For those who want to kill all three groups of badies (viruses, bacteria and cysts), the following options can be used:

1. Chemicals only -- Aqua Mira, Klearwater or Micropur -- wait up to 4 hours!

2. Mechanical and chemical - Filter the bigger stuff out first, then treat with chemicals to kill viruses -- only 15 minutes treatment time required, longer if water is really cold -- beats waiting for 4 hours.

3. Chemical and Mechanical - Treat with chemicals to kill viruses first, then filter out the bigger stuff AND any chemical taste. This is my method, and I use Micropur and then a Seychelle inline filter.

4. UV (Steri-Pen, etc.) - Zap the water with UV rays for one minute and kill all three types of baddies. Unfortunately (for me), I use narrow-mouth platy's and the UV tube isn't as effective since it can't reach down far enough into the bottle. Talking with Steri-Pen folks on the phone, they suggest that I treat the water in a cup or equivalent wide-mouth container, then pour the treated water into my Platypus. I find that too much of a hassle, but YMMV.

Thanks Ben, but KlearWater directions clearly state only 15 -30 minutes wait time for Giardia and Crypto. Micropur clearly states 4 hours. I assume they are allowed to make these claims due to actual test results?

The difference clearly doesn't make a lot of sense, other than the tablets take a while to dissolve. Why can KlearWater make the written claim of 30 minutes for Crypto when Aqua Mira cannot?

I use a narrow mouth platy too - the Steripen would create a hassle and require an extra cup or wide mouth container, which negates the weight savings a bit.

With your method of treatment, the 15-30 minute wait would kill the virus or bacteria and the filter gets the protozoa. It seems this would make sense on several counts - shorter wait time, built-in back up system, less risk. Downside, the weight of both systems, but pre-packaged tablets weigh very little.

Food for thought.

The more I think about it the more I think I might like the system you are using Ben. Wait 15 minutes, drink through the filter as needed, and the chemical is still working in the remaining water in the bladder.

Do you still sip through the filter in camp, or do you squeeze some out through it to another container (or let it gravity feed into another container?) It seems it would be unhandy to use the in-line filter for in-camp water needs.

Do you set up your filter so it is inline next to the bladder itself inside your pack? Or does it go closer to the mouthpiece?

This may have been discussed at length in previous posts, but I just made a quick review of the evaluations performed by the U.S. Army Center for Health Promotion and Preventive Medicine and they concluded that the SteriPens FAILED on all 4 of their evaluation criteria.

I presume there is more to the story that supports the safe useage of SteriPens?

Edited by lucylab2 on 03/27/2007 08:51:23 MDT.

>...and they concluded that the SteriPens FAILED on all 4 of their evaluation criteria.


Their evaluation was predicated on the device being used in turbid water without pre-filtering. Since the SteriPEN (and the UV AquaStar) requires the water to be mostly clear to function properly, it failed to meet the requirements. Hikers who choose UV sterilization aren't under the same test constraints, and with many options for pre-filtering turbid water (if even encountered), the devices can meet our needs when properly supplemented. Hydro-Photon (manufacturer of the SteriPEN) sells a widemouth pre-filter for just this purpose.

Edited by Otter on 03/27/2007 09:27:07 MDT.

Referring to Benjamin's list above:

>For those who want to kill all three groups of badies (viruses, bacteria and cysts), the following options can be used...

PJ has brought to our attention another kind of nasty: hydatid tapeworms. Option 1 does not kill these, nor possibly option 4 (I think they're mentioned as UV resistant). Only options 2 and 3 are effective against all 4 groups. Thus, I'd like to propose another option, which is also effective against all four groups:

5. Mechanical and UV: filter the bigger stuff out (any type of filter, since we only need to remove relatively large objects), then zap the water with UV rays for one minute. This order ensures proper pre-filtering of the water for effective UV treatment.

The proper choice of filtration in options 2, 3 and 5 can also meet Benjamin's desire to remove bad flavors and other organic and inorganic contaminants, which could be considered a fifth class of baddie. This is important in areas where apparently pristine streams are contaminated with mine effluent or leachate.

Edited by Otter on 03/27/2007 09:40:50 MDT.

Pamela:

Actually, I give kudos to Micropur for being honest and upfront that while chlorine dioxide can kill cysts/crypto, it does require a ridiculously long wait time (i.e. 4 hours).

My read for BPL is that they seem to go out of their way to be vague -- mentioning cysts and crypto so buyers will associate Klearwater with killing these nasties -- BUT mentioning the treatment time only as it applies to easy kills like bacteria and viruses! I copy and paste BPL's specifications below:

SPECIFICATIONS

Active ingredient: Chlorine Dioxide 0.15%
Bottle type: Opaque brown glass, 32 ml or 50 ml
Dosing mechanism: Built into cap
Dosage & contact time: 1 ml for 15-30 minutes. Halve dosage and double the treatment time, or double dosage and halve the treatment time. Increase treatment time for cold water temperatures, cloudy water, and treatment of some organisms (e.g., protozoan cysts)

See how they simply mention "increase treatment time" for protozoan cysts (which include crypto)!!! Micropur, on the other hand, spells out 4 hours prominently. The active ingredient for both is identical.

Answering your other question -- you can continue to sip water through the Seychelle even at camp (of course) -- but it can also be used like a gravity filter -- just hang a bladder on a branch and have the water drip through into a clean container below. The speed of gravity feed is actually quite decent, but if you are in a hurry or just want to get a cup quickly -- you can also squeeze/roll the bladder to force water through the filter at an even quicker pace.

Edited by ben2world on 03/27/2007 13:00:38 MDT.

UV-C is not alone, since Chems may not work as well with turbid water vs. clear water also. Why?

My understanding is at least two reasons:

1) some organic material may harbor and protect larger masses of organisms (one type of biofilm) from exposure to the chemicals

2) some materials may react chemically w/the chems and thus "use up" so to speak some of the active forms of the chemicals which would otherwise be used to kill nasty lil' buggers.

Theoretically, as far as current means of backcountry water purification available to the L/UL backpacker go, a two-step approach is required.

Filter (at least 15-20 micron absolute pore size, though 25 micron might work, but it's at the lower threshold of hydatid tape eggs size, according to my reading) first, then Chems or UV-C for the smaller buggers.

Go with a smaller absolute pore, theoretically, 1 micron to get all/nearly all Crypto (as Crypto can fold over on itself - i've actually seen this under a light microscope - though, IME, it's somewhat rare, but i've only observed Crypto a few/handful of times and NOT many times - so would hesitate to draw any statistical conclusions, with high levels of confidence, based upon my personal observations) and other protozoans, and then treat with Chems or UV-C. This will shorten Chem contact time to 30min for bacteria; of course, only dosing time is required for UV-C.

---------------
On a related note, I would like to see a list of chems that activated charcoal absorbs, and a list of chems that it doesn't. This would be highly instructive. Anyone feel up to doing a web search, or is someone already in possession of this knowledge?

Have those of you who are narrow mouth (Platypus) users considered the Nalgene Canteen? A splashguard and canteen are my next purchases. Just curious.

I have considered these canteens and went so far as to order four (4) of them from BPL to experiment with. I just got them and being the gram weenie that I am I already and wincing at the weight over my narrow month platys. The canteens seem to work well with the SteriPen but it's bad enough I have to eat the weight of the SteriPen over my AquaMira setup but now I need a heavier water bottle. Needless to say I have a ways to go in my evaluation of UV water treatment.

James:

While the "zap for a minute and you're done" methodology is certainly enticing... the other thing I am concerned is brown, turbid water -- say after a storm churns up the river or stream. UV effectiveness would be compromised... meaning back to square one again???

>> What are UL backpackers using these days for water purification?
...
am hoping to learn what's new (being an old goat here). <<

For the next three seasons, I just made the switch from Katadyn Hiker filter to Aqua Mira with the BLP bottles.

In addition from going from 11 oz to a just a couple, I'm breaking away from my old goat mindset. Baaahhhh : )

James, I'm guessing that the weight you save from not having to carry much water from source to source more than makes up for the weight of the the Steripen and the Nalgene canteens.

We shall see, Benjamin. That's certainly a consideration. The web site clearly says not to use it on water with "significant discoloration or particulates".

I wonder if "significant discoloration" would include tannins? The water in parts of Wisconsin is tea colored (but clear) in many places I hike.

I'll try it for a year or so and see how it goes. I always need to test something many times before I finally decide if it will work for me. In the end it remains much heavier than my tried and true AquaMira/dropper bottle setup and I'll almost certainly go back to that... but it will be fun to play with.

Hey Dondo... I will tell you one thing I like and that's the idea of stopping, scooping up THAT water from a stream, and drinking it down 90 seconds later. There is an aesthetic component that will be hard to beat. I have a friend that has one of those drinking straw/water bottle setups... I am not a fan of these... but when she dunks it in the stream and starts drinking on the spot I am more than a little green with envy as I fiddle with my dropper bottles. :)

Ben, in my experience, filters clog easily in brown, turbid waters. And chlorine dioxide treatments also suffer in these conditions. A solution in all these cases is to prefilter the water. The Steripen makers offer a prefilter that fits over the mouth of a wide mouth bottle.

Dondo -- Very true that filters can get clogged up... but the Steri-Pen prefilter will do nothing to clear up brown river water either. I guess this is no single solution that is ideal.

But I thing I know: referencing George's 's post above, an old goat still beats a sick goat! :)

Edited by ben2world on 03/27/2007 21:23:56 MDT.

James, I use to use one of those setups and agree that it's pretty cool. My problem with it was that my hand got tired squeezing the bottle and I didn't like sucking water through the straw.

I've only used the Steripen on one trip but already it's my favorite method. You just dip your bottle, stir for a minute or so, and drink. It's amazing. I almost felt like I was cheating.

Edited by Dondo on 03/27/2007 21:33:16 MDT.

Ben, I think our difference on this may be where we hike. I honestly can't remember the last time I had to treat turbid water. Most of the time I get my water from the tiny side streams dripping down from the mountains. These are plentiful where I hike and are almost always clear.