SAWYER WATER FILTER INFO
Here's my personal choice for water filtration--it's a great combination of affordability and outstanding filtration (0.1 micron):
The Sawyer Water Filter
Sawyer now sells a smaller version of the same filter at an even lower price:
The Sawyer Mini Water Filtration System
There's also a more expensive version that will filter down to 0.02 micron - that's small enough to take our even the smallest viruses. I haven't tested it yet, but I'm confident the product lives up to the filtration claims.
Here's a link to a field test that was conducted in Fiji with roughly 400 Sawyer water filters. Many other humanitarian groups have distributed these in remote areas.
BLEACH (AND OTHER CHEMICALS)
I recommend keeping some chlorine bleach on hand. Adding 3-5 drops per quart, or 1/8-1/4 teaspoon per gallon, will knock out the small pathogens very quickly. (For more details on chlorine's effectiveness, take a look at this neat chart from the CDC website: http://www.cdc.gov/safewater/effectiveness-on-pathogens.html.)
Here's why I really like to have bacteria filtered from drinking water: several strains take half and hour or more to be killed by bleach. In contrast, most viruses are killed by weak concentrations of chlorine in less than 5 minutes.
This was one of the most interesting discoveries as I researched water treatment: Vitamin C powder (particularly sodium ascorbate, although ascorbic acid will work almost as well) neutralizes chlorine. I recommend having some of this on hand, especially if you'll be drinking chlorine-treated water for extended periods of time. Here's what I'm stocking. Note: Be sure you don't add sodium ascorbate to your chlorine-treated water until you've let the chorine work for a little while (15 minutes for viruses, longer for bigger stuff).
For more info on this chemical reaction, take a look HERE.
I didn't mention this in my video, but some people like water treatment tablets. I don't really know enough about them to give a recomendation personally, but REI has a decent selection, and they generally only sell stuff that's decent.
STERIPEN
Another nifty tool that I've added to my stash is the Classic Steripen. It runs off 4x AA batteries. There are also versions that run off CR123s. I hope to cover batteries in a later video - specifically rechargeables and charging solutions.
HTI X-PACK
If money were no issue for me, I'd probably also add one of these per family member: HTI X-Pack. This is perhaps the most awesome filter concept I've seen. HTI also makes a backpack version that lasts for 90 days instead of 10.
Oh, and I forgot to mention this in the video, but the final product after filtration isn't water: it's a "sports drink" with electrlytes and stuff in it to enhance rehydration. These filters will turn water from a mud puddle into watery gatorade. Very awesome.
In talking with the VP of HTI I was told you don't HAVE to use their "recharge" packs. Other sugary concentrates like Coca Cola syrup will work. Also of note: the X-Pack is only rated for 10 days but can be pushed beyond that. They said they've have people use them for up to 30 days.