The SteriPEN Adventurer Opti and the H2O Amigo Pro are both innovative and effective means for treating water in the backcountry, but the two products otherwise share little in common.
SteriPEN's story has been one of overwhelming success and rapid adoption amongst backpackers. After selling its first unit in 1999, Hydro-Photon Inc, the makers of SteriPEN, now offer no fewer than ten versions of the SteriPEN and market not only to the backpacking community, but also to the military, emergency rescue agencies, and the general traveling public.
The success and attention surrounding SteriPEN lies in a breakthrough, and admittedly glitzy concept in water purification: the use of ultraviolet light from a handheld pen-shaped device to scramble the genetic material of water-borne pathogens, making them incapable of reproducing. This technology is a clean alternative to more traditional water treatment methods involving chemicals or filtration. The Adventurer Opti is the ultralight version of the SteriPEN and can be used with disposable or rechargeable CR123 Li-ion batteries. For those not keen on buying disposable batteries or relying on the power grid, SteriPEN makes a solar charging case exclusively for the Adventurer Opti.
The H2O Amigo occupies the more subdued realm of the gravity filter. Far from being on technology's cutting edge, the gravity filter's basic, but effective design uses a water-holding bag that contains a filter with a small tube at the bottom for water output. The bag is filled, hung, and water moves passively from thebag, through the filter, and out to another bag or a drinking bottle for consumption. It's essentially pump filtration without all the work required of pumping.
A quick-drying, lightweight SilNylon bag with durable drawstrings and a single open-ended output hose make the Amigo perhaps the most no-frills, elegantly designed gravity filter to date. Sadly, the Amigo is no longer in production by its manufacturer, Ultralight Adventure Equipment. MSR, Katadyn, Cascade Designs, and Sawyer Products sell their own gravity filters, but none matche the lightweight simplicity of the Amigo. Used Amigos can still occasionally be found online, but these tend to be few and far between. More importantly though, the Amigo's simple design and obtainable raw materials perhaps permit at-home construction. This subject has been discussed in great detail on BPL's own forums.
The aim of this study was to compare the solar-powered SteriPEN Adventurer Opti with the H2O Amigo Pro for use in long distance hiking. Both devices were used alternately along 800 miles of the Montana section of the Continental Divide Trail from July 19 toSeptember 28, 2010 to provide drinking water for a companion and myself. While one device was in use, we shipped the other ahead to a mail drop location. Once at the mail drop, we switched devices, shipping the other ahead to the next mail drop. Practical considerations for long distance hiking for each device were noted. These included observations and recorded data on each device's weight, cost, performance, maintenance requirements, durability, and ease of lightweight modification. Temperatures ranged from the mid 80s to the mid 20s F. The Amigo was outfitted with a new Katadyn Hiker filter.
ARTICLE OUTLINE
- Introduction
- Results
- Overall Impressions
# WORDS: 2350
# PHOTOS: 10
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Companion forum thread to:
SteriPEN vs H2O Amigo, a long distance hiker’s comparison
I've had an Amigo for a few years now, and I believe it's one of the only pieces of my kit that has stuck around so long. Most of my trips are with at least one more person and it makes perfect sense for group use.
A fair comparison. Interesting. The Hiker filter is very reliable but quite heavy. It would be interesting to compare it with a Sawyer filter cartridge.
My only real comment concerns the solar recharger. It was not made specifically for the Opti: it was available with the first generation Adventurer. I believe it was originally made for use by missionaries, probably in Africa.
Anyhow, I have taken the solar cell out of the case and given it the UL treatment. There is a photo of it at SteripenAdventurer. It got a bit lighter.
There is also a review of the Opti here.
Cheers
Very nice article, Thanks.
My very first filter was a MYOG Ray Jardine "Hikers Friend" gravity system.
It used a collapsible plastic jug and a generic filter element with a piece of aquarium tubing. The H2O Amigo seems much more compact and certainly lighter weight.
Over the past two years I have used Chlorine Bleach drops and an MSR Sweetwater filter.
The problem is: I am lazy.
I really don't like to wait or spend time pumping so i drink untreated water a lot.
So now I have a Steripen Classic to try out.
Your statement:
"Finally, designing the solar charging case to charge the batteries while still inside the SteriPEN would reduce weight by eliminating the need to carry a second set of batteries. It would also add a considerable amount of convenience to the entire system."
This is huge. I keep wondering when a lot of small electronics will be offered with integrated solar charging. Steripen should make a deal with Brunton or Solio and add a flexible solar panel that wraps arrond the handle of the Steripen for storage. A little bit of cord could allow the panel to be spread out on top of the pack, perhaps attached with velcro tabs while the steripen satys stowed in a pack pocket.
Whatever they do they need to maintain the water resistance of the steripen. If i have to start babying it around water or in rain it's definitely out.
I really appreciate the cost comparison chart. It really brings home the issue of disposeable batteries and the waste factor.
Thanks for the great article!
Is the Amigo actually for sale anywhere any more?
edit…n/m missed that paragraph…
Neat comparison. I'll still go with the SteriPen, but was cool to see the two side-by-side and showing how they fair on a long hike. For me, just go with an extra set of batteries and leave the heavy solar charger at home, where it won't mistakenly get damaged. I'm never on the trail for long and I bet there's many who are on similarly shorter walks of one to five days. Ninety seconds isn't really very long to stir for a bit of water. Again, great review.
I have and still use the original Amigo H2O from ULA.
I switched to the steripen when the Adventurer model first came out.
It promptly failed after a few trips.
Needless to say, I learned the hard way not to rely on high-tech equipment in the backcountry. My Amigo is my trusted friend.
I've been really happy with the Aquamira frontier pro stripped down and used as a gravity filter. I attach it and the prefilter to a 1L platypus, clearly marked as dirty, for the reservoir. I pull off the nipple. This feeds another 1L plat. I attached a string to the reservoir for hanging. I use a sandwich bag for filling the reservoir. The whole kit weighs 4.8 ounces.
You can of course use the filter as a straw or use it for sipping on the end of the reservoir. The only problem I've encountered is that the nipple is poorly constructed and easily broke while taking it off and on. I wrote the company about this, but heard nothing. The nipple problem however is easily worked around.
As a gravity filter it is a little slow, but plenty fast enough. Great tasting, good system for my purposes.
I agree 100% with Roger about the Steripen. They work well. I have the older Adventurer model and am waiting for it to break or for a lamp replacement. It still keeps lighting. I recommend his articles for a somewhat more technical look.
Since they are nearly instantanious, they save weight. You no longer have to carry extra water while chemicals "cook". 'Corse, in a desert, or a dry stretch, you need some extra, based on water availibility. Generally, most places I hike are 3-4 hours max between water sources. Soo, I drop a 1/2L bottle. "A pint is a pound…"
It is recommended carrying a spare set of batteries. Expensive and a bit heavy, but worth the safety. Flip one battery over to prevent current losses. The rechargables don't give the required current and are heavier. So, spend the $12 on a set of lithium's. Well worth it.
Buy the batteries online. Cheap.
Look here
http://www.batteryjunction.com/pri-cr123a.html
I've had an Adventurer since they came out and love it. NO issues.
I do pack a spare set of batteries too.
Bill’s “Home Made Gravity Feed Water Filter”
Note the date: Sept. 23, 2005 Cuben Water Bag
– 0.54oz Fittings – 0.176oz Hose (25″)
– 0.95oz Modified Hiker Pro Filter – 1.9oz
Total Weight – 3.6oz
Stock Hiker Pro – 102.5gr/3.62oz
Modified (not cut-down) Hiker Pro – 52.9gr/1.9oz
Finial weight saving modification of the filter not shown.
Bill’s Modified Amigo
When ULA added the new H2O Amigo to their product they copied everything about my filter except the Cuben Bag and my last weight saving filter modification.
What would your finial comment have been if you had used my filter in your review?
I have used Steripens for 4-5 years and was a beta tester for their Opti model. I find their Opti model the most reliable of all Steripens they've made, not once failing on me. I have worked closely with their support department and they are very insistent on top quality batteries being used. It's okay to get good ones discounted, but I would not get cheap ones myself. I'll try and find some literature on the issue.
Have used them on the JMT 3 years now. The opti for 2 of the 3 years (I had a pre-production opti version which is why I was able to do so).
I know for sure they approve of the Duracell and Panasonic brand batteries. Last I heard they were doing tests on the EverReady. I'll try find out the results.
Thanks, Roliegh…about my take on it, disregarding the manufacturer's spec.
I am still using the old Adventurer…someday…
The batteries are all over in price. I was quoting about the worst case I have seen at one of the supply shops just off the NFCT.
I can't understand why more people don't use the Super Delios system. Weighs 58g inc bottle and will purify 1,000 litres of water. http://www.delios.co.uk/what%20is%20delios.html You can take the filter (weighs 40g) and put it on Platypus bottle if you want.
Roger,
One aspect of the Sawyer filter is that it effectively has a life time guarantee and the filter does not ever need to be replace unless you manage to crack the exterior casing or allow the filter to freeze and damage the plastic hollow tubes inside.
I have been using the same Sawyer filter since 2007 and it has no signs for slowing down or wearing out.
It is field cleanable by back flushing and there is nothing that needs to be replaced internally or externally.
I use mine as part of a gravity filter.
Cost wise, it should be the cheapest filter out there because once you buy it you are done.
-Tony
I've been using Steripens a few times to treat water on trail ultra races without aid (100 mile run distance). I had both a SteriPen Adventurer which stopped working altogether, and later a newer model with LCD. Both were notoriously unreliable – even with fresh batteries. I am not sure if this was due to the bouncing during running (both were in their neoprene sheaths on my belt). My observations:
– both devices were tested at home before the races. I always protect the batteries during travel with some cardboard to make sure they don't discharge accidentally.
– some water seems not to have enough electrolyte content to be registered by the Steripen (it only can be turned on when submerged in water, detected by two electrodes) – I had to add electrolytes to it. This was just water from streams in the Cascades.
– It would occasionally just not light up at all, and often light up briefly, to be followed by an error (red light or frowny face).
– The adventurer lasted almost one run but became increasingly difficult to turn on (it would turn on and immediately turn off), and the second one did not work at all once on the trail. I had changes of batteries, they were not the issue.
Overall I found reliability to be very poor, sadly, though I also could not really spend too much time trying to get them to work during the race. I wonder if anyone else had such problems.
Cheers,
Beat
I have the original ULA Amigo and used it for about three years. (two of us). Now I just carry the Steripen Adventurer and the Katadyn Micropur tablets for backup and time saving. The combination pen and pill is faster than the Amigo if we need enough water for a dry camp. We pen enough to drink and pill the rest. We've been getting about 35 liters per set of batteries. That is less than the rated 50, but ok.
I've been very pleased with the mUV, a field-rechargable UVC water purifier by Meridian Design. Weighing 2.4 ounces, it recharges by a simple attachment to most standard batteries (much simpler than the solar recharger).
http://www.uvaquastar.com/skins/2008Style/standard2.aspx?elid=249&qid=30&SkipFlip=249
I do the same as Ralph. SteriPen Adventurer for my bike bottle electrolyte water, Micropur tabs for my hydration bladder.
I SERIOUSLY doubt if the Amigo gravity filter will take out viruses. The SteriPen absolutely will.
Thus the SteriPen is a water PURIFER, and the Amigo is not. The FDA/EPA would not classify the Amigo as a purifier.
BTW, I always "filter" my water, whether for Micropur chlorine dioxide treatment or SteriPen UV treatment, with a #1 coffee filter in a small funnel before treating. Keeps out small children and rocks.
I bought a Steripen Adventurer some years ago. I found it extremely cranky, failing to function on many occasions and currently, wholly out of service. New batteries haven't made a difference. While a fabulous device when it does work, the lack of reliability in the woods makes it a poor choice to me when contemplating a longer hike or an Alaskan adventure.
I might add that some of the comments to the article were more useful than the H2O Amigo review, if only because the latter is no longer available. It seems like it would be most helpful to explore some of the options outlined by commentators as they described other, available products or modifications that one could employ to achieve what the H2O Amigo once provided.
"I SERIOUSLY doubt if the Amigo gravity filter will take out viruses. The SteriPen absolutely will. Thus the SteriPEn is a water PURIFER, and the Amigo is not. The FDA would not classify the Amigo as a purifier."
That's accurate. Katadyn rates the Hiker/Hiker Pro cartridge at 0.3 µm, much too large for filtering viruses (and which they do not claim).
Cheers,
Rick
In regards to viruses, IIRC they don't exist in US water. Something to note for use in other countries though.
Hi Chris
You do NOT remember correctly ! ! ! ! ! ! ! ! !
Viruses exist everywhere around the world. What do you think causes the common cold? Water in the USA is as suspect as water in most any Western country. Granted, some third-world countries are worse.
Cheers
Hi Ken, and everyone
> Buy the batteries online. Cheap.
Caution!
Buying on line is OK provided that you buy 'brand name' batteries. The Duracell and Panasonic batteries on that web site should be OK provided that they are not 5 years old and not fakes. The other cheaper brands … are probably not able to provide the 1 Amp needed.
You get what you pay for.
Cheers
Hi Robin
That is a UK web site, not subject to USA EPA regulation. The Super Delios system only filters to 0.2 microns. It is not a 'purifier' in the EPA meaning of the word, as it cannot stop viruses.
On the other hand, if you want to use it as a filter and handle virus problems separately – it could be fine.
Cheers
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