water purification input needed

The best water treatment depends on conditions. In the North America, where the water runs clear I use chlorine dioxide tabs. If the water is silty, muddy then I use a filter, as I would in any international water source.

I so far have avoided the steripens, just one more electronic device to fail. (the only electronic device that I haven't had a fail yet is my led headlamp).

All have positive and negative qualities.

Chemicals are light, but sometimes have bad tastes, and you might have to wait several hours to kill protozoans in cloudy or cold water. They generally kill viruses and bacteria quickly. (The MSR MIOX falls into this category- I personally think it is a useless device. It has all the disadvantages of other chemical treatments, but weighs more and requires batteries. It MIGHT be useful for treating very large volumes of water, though, like for a large group.) Iodine is outdated, by the way- it turns out that it may not have much activity against cryptosporidium. The newer chlorine dioxide systems are better (AquaMira is popular, and they make tablets which are quite convenient). You can combine chemicals with a very basic filter- like the Frontier Pro- to remove the protozoans quickly instead of waiting 1 to 4 hours.

Filters are fast and convenient, but the vast majority don't stop enough viruses, which is why many companies package them with little dropper bottles of virucide. The ones that have filters fine enough for viruses are generally slow. You have to be careful not to let a filter freeze or they may crack (especially ceramic ones), and they may occasionally need to be cleaned.

(But I can't recommend Sawyer filters enough- they make a 0.02 micron microtubule filter rated against viruses, and it is the one they recommend for third-world travelers. Even their "lesser" 0.1 micron 4-way filter probably cuts viruses enough to meet EPA requirements to be rated as a purifier instead of a mere filter, but Sawyer isn't taking any chances. It is easy to back-flush to clean in the field. I love mine. Just scoop and drink.)

Boiling is easy, and kills everything, but takes time and fuel.

Ultraviolet water treatment (such as the SteriPen or Camelback units) is about to come of age. Current units are a bit heavy and theoretically fragile, but UV instantly kills virus, bacteria, and protozoans (as long as the water isn't too cloudy.) Downside- they need batteries. They'll be a much better option when UV-C LEDs become readily available and their weight and power requirements drop.

Hope this helped.

Complex today maybe, but once UV-C LEDs become available … (Even so, UV-C is my current choice.)

Cheers

Uh, yeah, Roger. What I said. :o)

"Ultraviolet water treatment (such as the SteriPen or Camelback units) is about to come of age. Current units are a bit heavy and theoretically fragile, but UV instantly kills virus, bacteria, and protozoans (as long as the water isn't too cloudy.)"

FYI – from the Steripen FAQ:
"SteriPEN utilizes C Wavelength UV (ultraviolet light). UV-C light is short wave light, between x-rays and visible light wavelengths, which destroy the DNA of microbes in seconds. Its like a singer that can break glass with their voice. Without functional DNA, microbes can't reproduce or make you sick."

The UV messes up DNA so the critters can't breed in your system. It doesn't kill anything.

I use Polar Pure. No maintenance, no moving parts to break, filters to clog or batteries to die. It may be a little heavier than most chemical treatment but it is still lighter than filters or Steripens. I have had the same bottle for three years or so. Does it taste bad? A little but no worse than the tap water at my house. The most important thing is I have never gotten sick after drinking water treated with Polar Pure.

Joseph

I think Dean's summary is a very good guide. Just to be clear, a filter does not necessarily mean a pump. Lots of ultra-lighters (myself included) use an inline filter. This may mean using it as a drip filter, or attaching to a platypus, turning it upside down and sucking through it.

There is a big advantage to any system that can be done quickly. With quick purification and the right conditions (hiking close to water) you may be able to avoid carrying water. Something to keep in mind because water is very heavy. Of course, that means that some techniques may make sense for some areas, but not others.

I was running my sump water through UV light to kill parasites on my Saltwater Reef Aquarium. Definitely does the job.

Without functional DNA microbes can't live, either. A viral capsule might remain intact with useless DNA inside, but whether those things are alive in the first place is a matter of debate. I think the SteriPen website used that roundabout phraseology to cover this oddball scenario with viruses, but I'm pretty confident that UV-C outright kills bacteria and protozoans. If you have other data showing that UV-C is bacteriostatic rather than bacteriocidal I'm quite honestly interested in seeing it.