Bacteria, Virii and other nasties can be interesting to live thorugh... Having been in Milwaukee several years ago during a certian Crypto outbreak...

One of my packs has a sealed fish tank filter and AquaPur in a gallon zippy bag. I use the fish filter to strain the gross(as in big bits) out of the water, the charchol gets some chemicals and the rest gets taken kare of with either boiling or the aquapure.

It actually works! One of the two times I used it, I was at a campsite that had signs that the water was not potable out of the pump for one and used a pot to boil things after straining. The other time, it was a rainy day and we realised that some dork haddn't dug a hole and that the pond was not as clean as we thought. I think it was a mental tummy ache after that one...

Rena