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I have always used the “Potable Aqua” iodine pills to treat water in the wilderness. Now I hear that they won’t kill one or two specific water-borne diseases. Is this true, and if so, what can I do to kill the extra germs?
Submitted by – George, Athens, OH
Yes, sir, iodine tablets have a very poor kill rate for cryptosporidium—microscopic bugs that are really hardy. You can use a relatively inexpensive water filter first—the kind that removes only the larger critters, such as crypto and giardia—then use the Potable Aqua to kill bacteria and viruses. Or you can switch to chlorine dioxide tabs (Potable Aqua makes these too), which will, unlike iodine, kill everything. But be aware: Chlorine dioxide takes up to four hours to kill crypto. —Buck