Water purification with the Steripen Adventurer Opti ultraviolet light is an easy way to kill the bacteria, viruses, and cryptosporidium found in natural water sources when day hiking, camping, or backpacking.
It’s easy to use, very reliable, and works in all temperatures, including below freezing, which will ruin most water filters made with hollow fiber filter elements. The Adventurer Opti can also be used with all types of water containers, provided you can insert the light element far enough into them including wide-mouth Nalgene or Hydro Flask aluminum bottles, CamelBak water bladders, and zip-top reservoirs from Osprey, Gregory, CNOC, HydraPak, and Platypus.
Note: Katadyn, which also manufactures water filters and purifiers, bought the company that makes Steripens several years ago. This explains why the Steripen Adventurer Opti is sometimes listed as the Katadyn Steripen Adventurer Opti at retailers.
Like all backcountry water treatment solutions, the SteriPEN Adventurer Opti, have their pros and cons and are not suitable in all circumstances. They work best with sediment-free water from mountain streams, rivers, ponds, and lakes that are free from the chemical or mineral pollutants found near agricultural, urban areas, and mining operations.
| Pros | Cons |
|---|---|
| Neutralizes biological organisms | Does not work with all bottles or reservoirs |
| Very fast | Battery dependent |
| Non-mechanical, no pumping | Does not remove chemical or mineral contaminents |
| Effective in cold or freezing weather | Not effective with cloudy or murky water |
| Does not affect taste | Does not neutralize larger organisms, i.e. worm eggs |
The Steripen Adventurer Opti weighs 3.6 oz including batteries and can purify 50 liters of water up to 8,000 times. That’s more than enough for weekend trips where you’d drink 4-5 liters per day. If you use it in temperatures under 32 degrees, it’s best to store it near your body to keep the battery warm, but it can be packed anywhere in warmer weather.
The SteriPEN Adventurer Opti can be used to purify 1 liter or half-liter of water at a time. You can use it with any plastic, metal, ceramic or glass bottle as long as it has a wide enough opening so you can submerge the Opti’s light element in it. While a wide-mouth 1 liter Nalgene bottle is very convenient to use, there’s no reason you can’t use a cooking pot too.
Once submerged, you stir the water gently with the SteriPEN until the UV light goes off, which signals that your water is purified. It takes about 90 seconds to finish. It is as simple as that. The ultraviolet light destroys the DNA that lets bacteria, viruses, or cysts replicate in your gut which is what makes you sick. If you’re worried about water remaining on the threads of the bottle or container you used, wipe them dry with a clean cloth. This isn’t a big concern since your immune system can usually handle the small number of organisms remaining on the threads if any.
The Adventurer Opti is powered by two CR123 lithium batteries, which are relatively inexpensive if you buy them in quantity at Amazon. They’re lithium batteries so they’re good in cold weather and won’t freeze when the temperature drops below 32 degrees, like alkaline batteries that contain water. If you take longer trips, the SteriPEN Classic might be a better solution because it can purify 150 liters on a single set of AA batteries although it is about twice as heavy as the Adventurer Opti, with batteries.
Like all water treatment solutions, it’s important to carry a water purification backup if your primary method fails. For example, I always carry Katadyn Micropur Chlorine Dioxide Tablets as a backup water purification method in case my primary method – be it a Steripen, a gravity filter, a pump filter, or squeeze filter – breaks, clogs, the batteries die or it fails somehow. I don’t use Micropur tablets all the time because I prefer the taste of non-chlorinated water and they’re a fairly expensive solution, but they reliably purify silt-free water stored in any container and at any temperature.
Recommendation
The Steripen Adventurer Opti is an easy-to-use water purification solution that can treat up to 50 liters. It’s powered by two lithium batteries and good for weekend trips with a couple, assuming you drink 4-5 liters of water per day or carry spare batteries for even longer-term use. Water purification with ultraviolet light is a very safe and effective way to purify natural water sources for human consumption, it’s very fast, and doesn’t rely on arduous squeezing or pumping to work. It can work with any water container that has a large enough opening to submerge the light element such as a wide-mouth Naglene bottle, a Hydro Flask bottle, and most hydration bladders with zip-tops.
Disclosure: The author purchased this product with his own funds.
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