Subscribe Contribute Advertise Facebook Twitter Instagram Forums Newsletter
Water purification
Display Avatars Sort By:
Mandy Kent
(vermontsilkie) - F

Locale: rural New England
Water purification on 03/26/2007 10:12:40 MDT Print View

What are UL backpackers using these days for water purification? I'm interested in both mechanical and chemical treatments.... I suspect my old First Need will be heavy by current standards and am hoping to learn what's new (being an old goat here).

David Lewis
(davidlewis) - MLife

Locale: Nova Scotia, Canada
Re: Water purification on 03/26/2007 10:35:52 MDT Print View

A lot of people... myself included... use Chlorine Dixoide... aka... Aqua Mira... or Pristine here in Canada. This stuff doesn't make the water taste bad... like Iodine. Most of us also repackage the drops in tiny mini-droppers to cut down weight even more. You can buy dropper bottles of various sizes on this site.

Other lightweight options are pre-mixed Chlorine Dioxide... Chlorine Dioxide tablets... and in-line filters... or that MSR pen thingie... or a gravity filter for longer hikes.

Definietly leave the big old pump filter at home :)

Edited by davidlewis on 03/26/2007 10:36:24 MDT.

John S.
(jshann) - F
Re: Water purification on 03/26/2007 11:17:28 MDT Print View

I use chlorine dioxide tablets, either Katadyn Micropur MP1 or Potable Aqua brand. The potable aqua is slightly cheaper it seems.

Ben 2 World
(ben2world) - MLife

Locale: So Cal
Re: Water purification on 03/26/2007 11:54:09 MDT Print View


Is it really true that you need a blade or something to cut open the packaging of the Potable Aqua chlorine dioxide tablets? Right now, I am using Micropur tablets, which can be torn open by hand pretty easily. I like to try your brand because of the cheaper price -- but wondering if it too can be torn open easily by hand -- or not?

Back to OP's question, for UL, you might think about a combination of (1) filtering out sediments and particles by first running the water through a metallic coffee mesh screen (available at Wal Mart, etc.), then (2) treating with chlorine dioxide tablets.

If you decide on chlorine dioxide -- I'd highly recommend tablets over liquids. With a tablet, you simply open one up and drop it into your water bottle -- 1 tablet per quart (or liter) and the waiting time is around 15 minutes.

With liquids (e.g. Aqua Mira) -- you have to count the number of drops from two different liquids, mix them in a small container (eg bottle cap) -- wait 5 minutes for the mixture to oxidize, and then pour the mixture into your water bottle for the requisite 15 minutes treatment time. To me, liquids mean added effort and time with no benefits whatsoever over tablets.

Edited by ben2world on 03/26/2007 11:54:59 MDT.

Jason Smith
(JasonS) - MLife

Locale: Northeast
Clorine dioxide on 03/26/2007 12:23:27 MDT Print View

I have used an MSR Pump, aquamira, micropure tablets, an aquastar, and a steripen, of them all I say the steripen and the aquamira are my two favorites, which I feel says alot considering the steripen is 10 times the cost of the aquamira. However, if you go backpacking often the steripen will pay itself off relatively quickly.

Edited by JasonS on 03/27/2007 12:14:59 MDT.

John S.
(jshann) - F
Re: Re: Water purification on 03/26/2007 13:29:23 MDT Print View

Ben, I have two packages of the potable aqua tablets but have not used them yet. The packaging looks the same as the katadyns . I always use my sak scissors to open even the micropur tablets. If the potable aqua packages required some sort of cutting device, you could score (make a nick in) the packaging before your trip and that should work well enough.

Ben 2 World
(ben2world) - MLife

Locale: So Cal
Re: Water purification on 03/26/2007 13:37:57 MDT Print View

John - Thanks for the feedback.

Jason -- Oops, I was pretty negative about mixing liquid chlorine dioxide... but curious, why do you prefer Aqua Mira over Micropur tablets?

Scott Peterson
(scottalanp) - F

Locale: Northern California
Re: Clorine dioxide on 03/26/2007 13:41:01 MDT Print View

"To me, liquids mean added effort and time with no benefits whatsoever over tablets."

Revisit the thread from very recently. Without referencing, I seem to remember that water temperature and taste were two variables with tablets versus liquid Chlorine Dioxide. Length of trip may factor for weight issues as well.

Seeing as this is a rather complex topic, and a well mined one, including more scientific content contained within the site, it is probably better to start by querying the site, gather thoughts or more specific questions, and going from there...unless you are looking for banter.

I would suggest that "water purification" could be it's own forum topic given the relative importance to the sport and the myriad of systems/approaches/and situational considerations and the frequency with which new folks tend to ask the same questions.

Mandy Kent
(vermontsilkie) - F

Locale: rural New England
h2o plus gear thread suggestion on 03/26/2007 14:21:18 MDT Print View

Scott, I think your idea that a separate column or forum might well be created for water purification, is a good one. I did check for recent threads on the topic before I posted but did not happen to see any. It makes sense the topic has been dealt with a lot; I am a new member of BPL though hardly new to backpacking. I did not do a complete search.

Actually, carrying your suggestion farther, it might make sense to divide this G-spot into topics, as the way it works with new posts bringing a thread to the top, topics "disappear" quickly. On the upside, it is great to see that BPL is so active! (Probably means those of us in the temperate zone are chomping at the bit to get out there...)

And replies are much appreciated. The chemical situation sounds as though it hasn't changed much; this debate, a good one, is ongoing from ten years ago. What probably has changed is the pump kind of purifier. When I started climbing around in the mountains, we didn't worry about drinking from small fast-moving streams and rarely heard of issues with giardia, etc. Different story today!

Do others think separate specific gear-related topics should be organized on G-spot? How would that happen?

Edited by vermontsilkie on 03/26/2007 14:23:58 MDT.

James Pitts
(jjpitts) - F

Locale: Midwest US
Re: Re: Water purification on 03/26/2007 14:33:31 MDT Print View

Cost is one consideration. The tablets are fairly expensive per liter compared to the liquid.

Katadyn MicroPUR MP1 Tablets = $14.24 to treat 30 liters. (~47 cents/liter)

McNett AquaMira = $11.04 to treat 113 liters. (~10 cents/liter)

...I think I did the math correctly. The prices are from BPL naturally.

James Pitts
(jjpitts) - F

Locale: Midwest US
Re: h2o plus gear thread suggestion on 03/26/2007 14:42:28 MDT Print View

...and to Mary's post I'll add that there are few gear discussions so grounded in personal preference as a group of people that have never gotten sick from drinking water arguing about what method of water treatment works best for them. I'm just adding a bit of levity to the thread but I am sure you get my point. :)

Ben 2 World
(ben2world) - MLife

Locale: So Cal
Re: Water purification on 03/26/2007 15:18:40 MDT Print View

Each to his or her own of course, but considering the hundreds of dollars we gear geeks spend to shave an ounce, I won't fret on whether something costs 11 cents or 47 cents a quart.

Separately, I don't think there is any discernable difference in the efficacy of chlorine dioxide in tablet or liquid form. Neither will work on frozen water, but short of that, both will take similarly longer periods when treating cold water versus water at room temperature...

But in the end, Jim is right. Some people don't treat their water, period, and never get sick. Others worry that a kill rate of 99.9% is simply not enough... but insists on a log of 99.99999 before they take a sip of anything.

So, OP, read up on our individual prejudices and trade off's -- then determine what will work best for you -- based on your risk tolerance, cost, weight, ease of use, and efficacy expectations.

Monty Montana
(TarasBulba) - MLife

Locale: Rocky Mountains
Re: Water purification on 03/26/2007 15:45:32 MDT Print View

you can find a well researched article in the issue #2 print version of BPL: "Efficacy of Chemical Water Treatment in the Backcountry." Back issues may still be available as well as reprints of individual articles. In this article Aquimira, Polar Pure and MIOX are compared. By the way, I also spent many years dipping straight out stream and lake, but after moving from Montana to Washington (where more people and dogs are roaming the backcountry) I acquiesced and began using Potable Aqua on suspect water; most of the time I just use a Bota water bottle, which has a built-in filter.

Benjamin Tomsky
(btomsky) - F

Locale: San Francisco Bay Area
Re: Water purification on 03/26/2007 16:36:04 MDT Print View

I use Aqua Mira because it is
1. chemically stable
2. tasteless
3. a liquid that allows for variable dosing

Properties 1 and 2 apply to the various chlorine dioxide tablets.

Properties 2 and 3 apply to KlearWater (but I have experienced it loosing efficacy over a long trip, so I know it to be unstable).

Variable dosing is really the main benefit of a liquid, in my opinion. It allows the hiker to consume less chemical per unit of water consumed and carry less chemical for a trip. I suppose one could cut up tablets or use them in more than the recommended volume of water, but this seems impractical compared to measuring the liquid dose.

The following description of Dosing Strategies is from "Ryan Jordan's Comments" on the KlearWater page (

The following is not unique to KlearWater, and I use this strategy for Aqua Mira as well. Generally, as you halve the dose, you must double the treatment time for the same efficacy. This is a good way to minimize the amount of chemical you take on a trek. Likewise, if you want your water treated faster, or you are treating a more suspect water source, consider doubling your dosage and/or your treatment time. Generally, I use 1/2 ml of KlearWater per liter (e.g., of clear stream water) and wait 30-60 minutes before drinking it. Before going to bed, I use as little as 1/4 ml of KlearWater per liter, and let the water sit overnight. This strategy allows me to treat about 25-30 liters of water from a full MiniDrop bottle (6+ days of hard hiking on a bottle that weighs 0.5 oz full) and more than 80 liters of water from a full 32 ml KlearWater glass bottle (20+ days, 2.9 oz full). That's a very aggressive approach to extending the range of KlearWater. Generally, if the guidelines are followed, a full 32 ml glass bottle of KlearWater (2.9 oz) will last most hikers a week or more on the trail.

Ben 2 World
(ben2world) - MLife

Locale: So Cal
Re: Water purification on 03/26/2007 16:48:13 MDT Print View


I wish I could be like you -- not being able to taste the water after A.Q. treatment! I can certainly taste the results of both A.Q. and Micropur -- they're both equally awful -- to the point where I stick a Seychelle in-line filter between the treated water and my bite valve! The filter eliminates the bad taste, but I have to carry an extra 3.6 oz of weight, deal with the slight increase in hassle factor -- and suck harder for every mouthful of water! :(

The Other Ben.

Ken Helwig
(kennyhel77) - MLife

Locale: Scotts Valley CA via San Jose, CA
Re: Re: Water purification on 03/26/2007 16:51:05 MDT Print View

Steripen all the way. The ease of effort and the no waiting part is the best. A.M. gives me gas problems...severly!!! Plus I could never get over the slight chlorine taste that Aqua Mira had. Yes the Steripen is expensive but as much as I am out in the wilderness, it is worth every penny.

Brett .
(Brett1234) - F

Locale: CA
diluting micropur 2x, 4x on 03/26/2007 20:56:46 MDT Print View

I find the Micropur tablets most convenient and durable.
Some of the benefits:
- I can package one with a coffee filter in my emergency gear in my pocket
- I take just what I need for a trip since they are compartmentalized
- They have a longer shelf life than an opened bottle of aqua mira
- They will not spill or break (I believe AM should be kept in a brown glass bottle for longest shelf life)
- They can be distributed for redundancy; losing or forgetting one bottle of a liquid system would end water treatment (not a problem for people more careful than myself)
- They work well with my standard 1L platypus.. drop one in and put it in the pack. I keep one bottle ready for drinking/cooking, and one being treated
- No taste, they actually improve the taste of water
- After some internet research, I learned they can be diluted 2 or 4 times and still retain effectivity, just extend the treatment time by a proportional amount. This makes them about as cheap as one of the liquid treatments. (see my previous post, key word 'army' from an Army study which determined Micropur was the best water biocide).

Ben 2 World
(ben2world) - MLife

Locale: So Cal
Re: diluting micropur 2x, 4x on 03/26/2007 21:33:42 MDT Print View

Brett wrote above: "No taste, they actually improve the taste of water".

I disagree. I can't stand the taste (yeah, I know, I am repeating myself...).

Maybe Japanese water -- like Japanese snow -- really is different! :)

Pamela Wyant
(RiverRunner) - F - M
Treatment times on 03/27/2007 00:36:38 MDT Print View

Micropur tablets state 4 hour treatment for Crypto. I haven't used Aqua Mira, but I believe the package directions are similar?

So do those of you drinking AM or Micropur treated water within 30 minutes just hope there isn't Crypto, or is the 4 hour treatment really overstated?

KlearWater packaging says it treats bacteria, viruses, Giardia, and Crypto all within 15 minutes (30 for cloudy water), with no difference in treatment time or dosing for cold water.


I've used KlearWater and really like it, but unfortunately it doesn't seem to be available for ordering either from BPL or any other on-line source I could find right now. :(

I teetering between ordering the new SteriPen adventurer or more Micropur tablets and Aqua Mira for an upcoming trip. Battery life of the adventurer model of the SteriPen looks like it could be a problem though according to preliminary information from testers at

Pamela Wyant
(RiverRunner) - F - M
Re: Treatment times on 03/27/2007 00:42:25 MDT Print View

P.S. Keeping KlearWater refrigerated between trips significantly prolongs its shelf life. I have a partial bottle I've had over a year and just checked it last week and its still okay. It must be kept in the brown glass bottle though. If repackaged in plastic bottles it loses effectiveness within just 2-3 days in my experience.

Also, for Ben

I think those who believe KlearWAter actually 'improves' taste of water must be used to city water that isn't filtered. It didn't bother me much, but being used to well water, I found a slight taste, similar to what I notice in public water. I love the water at one of our local Girl Scout camps, but a lot of girls complain because the well water tastes bad to them! I guess much of it is what you get used to.