I did an "experiment" about the aluminium + iodine issue yesterday. I put experiment in quotations because I don't claim to have any scientific training or expertise and the simple minded nature of the "experiment" will be demonstrated by the description below. Kids, don't try this at home.<br><br>I used two of the anodized aluminium capsules by Bison Designs that I bought at REI. <br><br>Iodine tablet + drop of water in open container+ 1 minute= nothing except gooey tablet<br><br>iodine tablet + drop of water in open container + 15 min = gooey tablet<br><br>iodine tablet + drop of water in closed container + 15 min = gooey tablet<br><br>iodine tablet + drop of water in closed container shaken violently for 1 min = more gooey tablet<br><br>iodine tablet + drop of water + aluminium and anodized shavings that I scraped off outside of container in open container + 1 minute = gooey shavings<br><br>iodine tablet + drop of water + aluminium and anodized shavings that I scraped off outside of container in closed container + 1 minute = gooey shavings<br><br>iodine tablet + drop of water + aluminium and anodized shavings that I scraped off outside of container in closed container + 15 minute = gooey shavings<br><br>iodine tablet + drop of water + aluminium and anodized shavings that I scraped off outside of container in closed container + 15 minute + shaken violently for 1 minute = well mixed gooey shavings<br><br>10 iodine tablets + capsule filled with water and sealed + shaken violently for 1 minute = dissolved green goo<br><br>10 iodine tablets + capsule filled with water and sealed + shaken violently for 1 minute + 15 minutes = dissolved green goo.<br><br>No explosions, flares or fireworks to report.<br><br>Girlfriend was a little concerned, though. Word "obsessed" was used.

If you are inclined, try completely drying the capsule, filling it with Potable Aqua tablets, as full as possible, then place the capsule outside someplace completely safe from fire (under a rock?), wait 3 months. Open and note any corrosion, flames etc.<br><br>Each Potable Aqua tablet is supposed to liberate 4mg of iodine, so a full capsule (say 25 tablets) will only contain 0.1gram of iodine. Magic fires generally are using 50+ grams of elemental iodine and a pile of aluminum shavings so I think it is highly likely that these capsules will not violently react.....but be safe above all things.<br><br>

Who says they have no competition? I just got back from Mountain Equipment Co-op and there are several water purification tablets on the market. <br><br>Katadyn makes a small plastic bottle of 100 tablets which they advertise will purify 100 litres of water (presumably, one tablet per litre); the active ingredient is Sodium Hypochlorite (used as household bleach). They also sell it in liquid form. <br><br>There's also a product called "Pristine" which uses Chlorine Dioxide - there are two bottles and it's a two-stage treatment. This is a liquid treatment, but it should be possible to pour some of the liquid into two small, sealed containers. <br><br>The Coghlan iodide-based water purification tabs did contain a warning on the package that the shelf life once the bottle has been opened was one year; in an unopened bottle, 4 years. So that appears to be the same product as the Potable Aqua. <br><br>Neither the Katadyn nor the Pristine water treatments advised against opening the bottles. The Katadyn tablets came in a plastic bottle, that looks similar to a regular aspirin bottle, so it doesn't look like they require any special packaging, either.