UrbanMan replies: I have water purification means in depth. Meaning I am not relying just on one technology or one means. I have individual and group water filters, as well as water purification tablets (which I think you are calling "pills"), and can build field expedient water filtration methods when necessary.
I have several Aquamira Water Bottle and Filter units which is like a sports drink bottle with a filter,..just fill up with questionable water then drink. Best to run dirty water through cloth before hand to help prolong the filter. The filter removes 99.9% of Giardia, Cryptospordium and other contaminants as well as removing the chlorine taste. Each bottle filters up to 50 gallons.
I have several larger, group sized units, one a Katadyn hand pump unit and another a Katadyn Base Camp Water Filter System which uses a gravity feed water filter system, which I really like. It can filter 200 gallons or more.
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For my Bug Out Bags, I have added the Frontier Pro Ultralight Water Filter, which is approx 6 inches long and one inch in diameter. This uses a straw not shown in the picture (right) so you can directly drink water from a bad source. You can also remove the bite valve and gravity filter water from common bottle. It comes with 4 replacement pre-filters that will extend the internal filter life. This will filters up to 50 gallons.
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