Free way to store Potable Aqua

Well, I am cobbling together a couple of Altoids tin PSK's for my younger brothers. As I was leaving REI with a couple of the micro-compass zipper pulls (planning to pry the compass capsules out), I happened upon a discarded soda fountain cup with straw still in it. I tossed the litter in the trash but had an epiphany.

I grabbed the straw (red and about 7 mm in diam) and took it home. Gave it a quick wipe down and made sure the inside was dry (it was ...100 degree highs all week).

I took a hemostat I had lying around and squeezed the edge of the straw together with only a mm of straw sticking beyond the hemostat. I took a lighter and melted the protruding "lips" of the straw shut. Dropped six PA tabs in there and used the hemostat to pinch off the straw just above the tabs. Trimmed the straw and sealed the straw shut. I made sure to have the seals oriented at 90 degrees to each other to maximize the structural integrity of the straw.

This little red capsule is harldly larger than the tabs themselves and this technique could probably be used to create two tablet "unit-dose" capsules. No fiddling with lids and shaking tabs out. Just slice capsule open and drop in the water.

Thanks for the forum and don't tell my little bro's about the dirty straw I used. <img src="/images/graemlins/tongue.gif" alt="" />

If I remember correctly, iodine based water treatments(of which PA is) will eat through any non-glass or non-teflon material. I think the PA bottles have teflon coated metal caps, and the tiny capsules that Doug reccomends for smaller packaging are of the same construction. If you want to use this method I would leave it stored somewhere the iodine can't ruin anything if it ruptures for a month or so.

That's REALLY interesting. I know that the cotton in the bottle is fairly saturated, but I wouldn't call it "eaten". Perhaps, enough of the concentrated iodine gets through the plastic to cause corrosion. I will watch this carefully in my little iodine capsules.

Good thing though is that it wouldn't cost too much to replace the straw. <img src="/images/graemlins/wink.gif" alt="" /> Perhaps a bit of teflon tubing or vascular graft could be used to store the iodine capsules and just tie it off with a bit of thread.

No offense, but why would you use somebody else's used, dirty straw when you can pick up a handful for free at any fast food joint?

The iodine will "eat through" polymers other than teflon (poly ether ether ketone or PEEK). Iodine is very reactive and by reacting with the polymer breaks down the strands into shorter units causing the polymer to fail. Since different iodinated polymers are formed this will also have an effect on the physical properties of the bulk polymer making it weaker and more brittle. Glass is immune to this effect having no unsaturated C-C bonds or other sites of attack. The cotton is being iodinated as well, the the strands in cotton wool are not providing that much strength since it is only a loose packing material and you would not notice. The relevant polymer form would be cellulose and a cellulose polymer container will indead be degraded by contact with iodine.

<< I know that the cotton in the bottle is fairly saturated, but I wouldn't call it "eaten". >>

Probably because it's not cotton, which would be damaged by the free iodine - and consume the iodine. Check again - I bet you'll find that it's fiberglass or MAYBE an iodine-resistent polymer. A little flame on a tuft of it will be revealing - don't inhale any fumes that result.

The straw idea is great. How about some thin wall teflon tubing instead? I suspect that a mechanical seal, such as crimping a metal sleeve, would be required to seal the tubing.

Regards,

Tom

I was thinking the EXACT same thing, untill I thought about just WHAT he was putting IN the straws <img src="/images/graemlins/grin.gif" alt="" /> and what the purpose of the pills are...
I think the germs in that straw are in for a BAD time <img src="/images/graemlins/grin.gif" alt="" />

PA is not going to be stable enclosed in a straw. Straw plastic, as is all plastic, is slightly permeable to mositure and oxygen. You will eventually have inactive tablets, and most likely a corroded kit.

The only way to contain this product is in a glass bottle with teflon seal. The only long term way to contain this product is glass.....

Or use micropur pre packaged tablets.

hint* crush the tablet in the wrapper to allow better fit in your altoids tin <img src="/images/graemlins/wink.gif" alt="" />

Flip

Speaking of REI, this is what I use to store Potable Aqua tabs for EDC. This small (really small) capsule holds about 15 PA tabs.

Bison Designs Keychain Capsule

These are anodized aluminium. Will iodine have an effect on these capsules?

I use a blue one for PA and a red one for three peces of Spark Lite tinder and a shortened Spark Lite striker. These go on a split ring with a Silva Companion compass, ACR emergency whistle, Schrade SS1 knife, and Princeton Tec Pulsar II. Along with a Zippo lighter, keys, wallet and Benchmade Griptilian, this is my EDC kit.

Iodine vapor is very corrosive with aluminum. Anodized aluminum is somewhat more stable but I think over time you will see some corrosion. Aluminum powder and Iodine crystals are part of a magic fire demonstation (ie metal burns spectacularily with huge purple cloud of flames). The amount of iodine in a Bison capsule of Potable Aqua is probably not enough for this spectacular fire maker, but aluminum and iodine should really not be mixed.

Again....as I stated above only glass with teflon lined lids is suitable for PA storage.

Interesting. Thanks for the response.