I just came back from a 60 mile hike including climbing Mt Whitney (beautiful place BTW <img src="/images/graemlins/laugh.gif" alt="" />), and I learned something about the Hiker water filter by Katadyn.

Hiker has two tubes that can be attached to it: inlet and outlet. What we did on our hike was simply wrap both tubes around the body of the filter and stuff it in the soft case provided. Now, it may sound pretty obvious to others, but for some reason it did not occur to us at the time (probably altitude sickness clouding our judgement). If you have both dirty and clean tubes in the same place - cross contamination will occur. And it did! <img src="/images/graemlins/frown.gif" alt="" />

Somehow I escaped the wrath of bacteria, possibly because I had a Camelback, which I connected directly to the filter, but my friend came down with a relatively strong intestinal sickness (nausea, vomiting, diarrhea) after drinking one of the last batches of water. We immediately desinfected our water with Micropur tablets, but it was too late for him.

Moral of the story: make sure to separate your dirty and clean tubes on Hiker water filter. Probably put a clean tube in a separate ziplock baggie.

And Immodium. And a fresh pair of skivvies.

Real men wear kilts.

That may not have been cross contamination. Not keeping his bottles clean, not flooding the lands on the cap when filling etc, are also likely causes. Alternatively, take a large mouthed container with you marked "dirty!" Fill it with filtered water. Add a puritab. Put input tube into soak. That way you are certain.

It's also worth mentioning that no filter is effective against viruses. You require a purifier for that. I use a three stage process:
1) Milbank bag to deal with most of the turbidity.
2) Filter.
3) Puritab. Contact time according to temperature.
4) Neutralising tab when I want to drink it.

All that assumes that I cannot boil the water.

Not sure what you are referring to?

Redflare, I think that lands refers to the threading on the cap and bottletop where dirt and contamination can accumulate.

Perhaps Mr. Ratcliffe can enlighten us on the lands. Only he knows what he meant for sure, so I won't put words in his mouth, so to speak. I believe the lands comment refers to the lands & grooves in a rifled barrel. The inside of a threaded cap is made the same way, only the rate of twist is different. Whereas a rifled barrel might have a twist of 1 turn in 9 inches, a bottle cap may have 1 turn in 1/8 of an inch.

Congrats on whitney. Did you have any problems with the altitude? Although I guess you probably acclimitized fairly well after 60 miles. I'll be doing a 3 day backpack to the summit later this year.

I have the same filter, and you do have to be really careful with cross contamination. They even supply you with a special ziploc bag (labeled "outlet hose" or something like that) to keep the inlet and outlet hoses separate. I usually keep the outlet hose in the ziplock, and wrap the inlet around the filter. This is the opposite of what is called for in the instructions, but it's much easier to keep the inside of the ziploc clean, rather than put the contaminated hose in it and keep the rest of the bag clean. Usually, the outside of the filter is already dirty anyway, so wrapping the inlet hose around it doesn't cause problems.

That is one of the drawbacks to this filter, having to handle so many hoses while filtering. It's definitely a two person job to filter water with it. The MSR is better in this regard because it connect directly to the bottle, so you only need to deal with the inlet hose. I would have purchased the MSR filter, but it's bigger and heavier, plus I had one fail on a backpack trip before so I didn't want to risk having that happen again.

hmm... i personally think the MSR feels more reliable than the Hiker. Although mine Katadyn pocket feels the most reliable (and heaviest too!). The MSR has the added advantage being field cleanible. So what failed on your MSR ?

I keep mine dirty water hoses in zip-locs. I even store some of mine clean water hoses in seperate zip-locs aswell. You can attach you waterfilter to many hydration packs directly, which also prevents cross contamination.

The filter which has the greatest cross contamination are the gravity filters. The kind you suspend with a waterproof bag. The dirty water that gets on the outside of the bag, will follow gravity and will eventully follow the clean waterhose to it's destination. Wiping it dry on the outside or scoop water with a cup in to the bag, does seems to solve that but is a serious hassle. Unless you have a few extra pair of hands.

You would call them the treads on the cap. Mistake a lot of people make is filling the bottle and then screwing the cap on tight. What you should do is fill to brim, add puritab, screw lid on loose, shake well, leave for 10 mins then tighten lid. Refer to Ray Mears book on bushcraft if you want the best advice on the subject.

Thanks! <img src="/images/graemlins/laugh.gif" alt="" /> It was a heck of hike!

My friend lives in Indiana, he was quite out of shape, so he had a lot of altitude sickness initially. This started happening even at rather low elevations of about 10000ft at the Cottonwood trailhead, where we started. He was having palpitations, dizziness and headache. By and by it wore off, until we hit Mt. Whitney itself.

We started the ascent from the Guitar Lake (about 10500ft). Then at about 12500ft, I started having symptoms myself: dizziness, nausea, weakness, pulsating headache and a general feeling of unease. Dizziness gave me the most trouble, so I ended up looking at the mountain wall rather then out into the open. We sat down, ate some crackers, drank some water, rested for about 15 minutes. I felt better, all symptoms disappeared except for nausea. I started doing abdominal breathing, taking deep breath in through the nose and exhaling through pursed lips (technique used by asthmatics). In about 15 minutes of this, all symptoms disappeared. At the top of the mountain I was able to look down the Eastern slope (read vertical drop of about half a mile) without any apprehension.

If you go, make sure to bring the following essential items:
1. At least 80oz of water or more if it is hot. I brough a full 3 liter Camelback and was completely out by the time I reached the summit.
2. Sunblock and hat. My friend got second degree sunburn on his forehead, since he used neither one.
3. Crackers or other easy to digest and ready food.
4. Chap stic for the lips
5. First aid kit
6. Diamox (acetazolomide) pills may help if you are susceptible to altitude sickness. Get a prescription in advance since this is not a very popular drug and many pharmacies may not carry it.