SteriPEN vs H2O Amigo, a long distance hiker’s comparison

RE: Ken & Roleigh

I agree with Ken in that I just bought some Duracell batteries from Battery Junction. Cost $32 for 12 (that's $20 for the batteries plus $12 for shipping…yeah that shipping is high), so that's $2.67 per battery, which is much cheaper than buying them at a local store like Wal-mart.

Roleigh, I would add Energizer to your list of high quality batteries that the manufacturer prefers as I believe that is what came in my Steripen when I bought it…so I assume they feel those are good ones to use in it.

David,

They are both gravity filters, but the storage bags are quite different as is the filter technology.

I would guess that the Clean Stream is Heavier than the Amigo given that the Amigo is using a silnylon dirty water storage bag where the clean stream is using maybe something heavier.

My understanding is that the Amigo is using a Katadyn water filter that needs to be replaced over time.

The Sawyer filter is using hollow plastic tubes that are poreous enough to allow water to pass through the exterior of the tubes to the hollow center to then flow out of the filter, but those pores are too small for any bacteria to pass.

Since the Sawyer filter is using inorganic material/plastic, it does not wear out, bacteria can not grow on it, and it can be backflushed to clear clogs.

The Sawyer filter's warranty is for 1 Million gallons…effectively a life time guarantee.

The negative on the Sawyer is that it does not have any active charcoal as other filters might….compared to the Steripen, this is a non issue because the Steripen can not do anything to remove chemicals or improve taste either.

Hope this helps explain some differences.

-Tony

Hi Tony,

Good summery of the differences and similarities. If I can be indulged one teensy-weensy detail, the Sawyer is subject to bacterial (and mildew) growth. It's almost, perhaps literally impossible to dry out and Sawyer literature direct it be sanitized with chlorine solution prior to storage.

Cheers,

Rick

Staphylococcus epidermidis (all over you right now) loves to grow on plastic, a main reason why things like bladder catheters have to be removed/replaced every few days.

Rick,

Thanks for the clarification.

Would explain why the manual does talk about putting about 10 drops of chlorine into a liter of water to flush it though the system.

Anyway, I have been using mine for a number of years now 2007-2008? and it is still going strong and has not given me any problems.

Will be looking forward to seeing Roger's report on various gravity filter.

-Tony

Yes – Tony, Rick – thanks for the clarification.

We are to assume no one became ill during the trip or two or three weeks afterward.

The units never were used on the same water, but the sample size probably makes up for this. You don't know if any of the water would have made anyone ill if left untreated (no volunteers I suppose)

So the point of the article was comparing the mechanics of using the two systems in the field. The other conclusion is the two units provide the same level of water safety.

A small (maybe micron-sized comment) don't you view charging batteries as maintenance?

Todd, ULA is bringing the Amigo back…see the post three above yours for the post by ULA…they also have info on it on their Facebook page…

inventor of the h2o amigo

Bill F. Getting credit?

No,

What I did was change to the Katadyn Filter, reduce its weight and change the location to put it inside the water bag. Moving the Katadyn Filter's location is the only real difference between the original Amigo and the new Amigo. The filter location was my idea.

I did send the new owners of ULA an email with a link to my thread here and told them I don't know who they though invented the idea of where the filter went but they had my permission to use that part in a new product if they wanted to.

Timothy,

Nobody became ill after the trip.

You're right, the units weren't used in the same water. My suspicion is that some of the water we used, perhaps the water that was taken from cow-contaminated sources, would have made us sick. My understanding is that the incidence of backcountry water-acquired diarrhea is 3-5%, so it's always hard to say….

The point of the article was comparing the two devices for use in long distance hiking, commenting on the things long distance hikers tend to find important: convenience, cost, maintenance, etc. The two units provided the same level of water safety if your criteria is that none of us got sick. The two devices do differ in what they do and do not filter. more on that in another comment.

I personally view battery changing more as a convenience feature and maintenance as something that's done on a routine basis to prevent damage or operating failure. Yes, the SteriPen won't work if the batteries run out, so maybe this is just semantics.

First, thanks to everyone for providing such good discussion around the article. Reading comments is what I enjoy the most about writing. Second, I want to address a few recurring themes in the commentary:

VIRUSES. It is true that the Katadyn filter inside the H2O Amigo does not offer virus protection. It is also true that the incidence of backcountry water-acquired illness due to viruses in the USA is unknown. There is not sufficient scientific data exploring how often viruses make people sick in the backcountry. However, even if there was such data, it would invariably be limited to specific geographic regions. This is because the types and quantities of contaminants in a waterway are dependent on land use patterns. Waterways downstream of population-dense communities are more likely to contain traces of human waste and therefore to contain viruses that make people sick. Waterways near areas with spare human population or are upstream of large communities are less likely to contain viruses.

When discussing backcountry water treatment, various technologies shouldn't be thought of as "better" or "worse" based on the absolute number or type of contaminants filtered, destroyed, or otherwise rendered harmless. Performance metrics aside, a water treatment technology is only as good as where it is planning to be used. For instance, a technology that does not offer coverage for viruses might be a bad choice for thru-hiking the Potomac Heritage Trail, which passes by a large number of densely populated areas and ends in Washington, DC. On the other hand, a technology that covers bacteria and parasites, but not viruses, is perfectly acceptable for hikes in sparsely populated areas.

WHY I CHOSE A DISCONTINUED PRODUCT: An area of interest of mine has always been low tech vs high tech in the backcountry. This article was thus an extension of this curiosity, where the H2O Amigo was the the best representative of the gravity filter concept, even though it has been discontinued (and perhaps making a comeback!?) My assumption was that since we, the readers of BPL, value ingenuity and ease of at-home modification and since the H2O Amigo can be made at home for low cost, this article was relevant.

The review covers some interesting points, but I think the technologies are too diverse. An article with an overview and comparisons of electronic purifiers (UV and MIOX), chemical treatments, and filters is needed, with a separate article on each of the categories in detail.

The review is for a discontinued item, but there are a number of available gravity filters in the same class and should have been covered:

Katadyn Base Camp
Platypus GravityWorks
MSR AutoFlow Gravity Microfilter
Aquamira Frontier Pro
Sawyer gravity filters

Since there are dependable components available, a MYOG article on gravity filters would be very interesting.

As to the Steripen, the manufacturer does state that it takes 2-5 days to recharge the batteries with the solar charger. I think that takes it off the table as a viable hiking option with the rechargeable batteries. That option is better for remote/3rd-world use where AC power and battery availability are limited. I do use one and I remove the batteries for storage. I think it makes an excellent day hiking option, where you want to be able to use the water quickly. I back up any of my mechanical water purification choices with MicroPur tablets.

The Steripen and chlorine dioxide options make a good pairing. You can stretch battery life by treating water overnight and using the UV option for quick access during the day.

The Amigo is slated to be released, again, better'n ever.

Dale,

I must respectfully disagree with your implication that the technologies covered in the review are "too diverse" for comparison. A cross-technology comparison of water treatment methods is important because each technology has its own benefits and drawbacks specific to the technology as a whole. Such a comparison allows a user to decide which of these benefits and drawbacks are more suited to his or her own situation (mine was distance hiking in western Montana). From there, the decision about which specific model of technology to use can be made. I think this might be what you are looking for, which was not the aim of this particular article. I am surprised that there are not MORE cross-tech comparisons on gear test sites.

Had I had the time and financial resources, I might have liked to have covered more gravity filters and UV pens and had a really large cross-tech comparison. A significant problem, however would have arisen: As this was real-life field testing, we only drank so much water each day. Including four or five other devices would have meant less water tested per device so, statistically speaking, the comparisons would have been less powerful and some of the issues described in the article (the fraying SteriPen charger padding and broken clip) might not have come to light. So, at my own discretion, I decided to go with what I felt were the best representations of each technology.

There is already a very good gravity filter MYOG article published on this site by Bill Fornshell: http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=1294

The 2-5 day battery charge requirement DOES NOT take the rechargeable option off the table if the device is carried outside the pack where it can charge throughout the day while the other set of batteries is in use. It does, however, make it a less attractive option along trails that receive limited sunlight.

Best,

Dan

Did you make a filter bag for it? Any pics or directions , videos? I am interesting in a gravity filter like the amigo. The Kadyden is 70.00 bucks and group size. I just want a smaller lighter weight version does sawyer have that?

do you have a link to the filter you use? Is there a set with water bag or bladder and filter in one?

well, despite other's concerns, I'll put in a plus for the steripen. I've used a steripen regularly for 3 years and have never had any issue, and I regularly drown it and beat it about, as it's on my waist belt when I fish and I'm nver one to worry about stuff and have been been kinda rough with it in the process.

I find it is perfect to replace my water in a small gatorade bottle (600ml) which I drink as I fish, quite handy and more superior for this purpose than the filters.

My only niggle is that, of course, steripen can't do anything about the flavour of the water – it's safe, but there've been times when I wished for a carbon filter to "cleanse" the taste on the palate a little, e.g. when I've been fishing areas with livestock near the water (bleh).

Craig

"… it's safe, but there've been times when I wished for a carbon filter to "cleanse" the taste on the palate a little, e.g. when I've been fishing areas with livestock near the water (bleh)."

Ha, ha… Yeah, I know the problem. Have you tried a few grains of crystal lite? Usually,
a little packet(To-Go or something) will bo two or three bottles.