Question:
I would like to know how and where and when etc to spread out that plastic over a pit or sump and to get "distilled" water (condensate) at the top which drips into a jug.

Answer: Bleach is the METHOD OF LAST RESORT, when THAT IS ALL YOU'VE GOT. Chlorine only works for city water because they use a KNOWN WATER SOURCE that's BACKED UP WITH DAILY WATER TESTS. Bleach isn't reliable on surface water because bleach doesn't kill all water borne organisms at a dosage level you'd want to drink :o/ it's easy to overdose with chlorine too :o/

Boiling is best because it's guarenteed to kill everything living in the water.

This costs what, about 30 cents per gallon? Does this type of iodine keep it's strength once opened? Does this do anything for larger organisms like cysts?

Polar Pure is the best iodine based method of chemcial water purification. It treats up to 2000 quarts, indefinate shelflife even after it's been opened (as long as you store it with the lid on), and costs only $10. That's as low as 2 cents per gallon. If you're going to the trouble of buying iodine for water purification, use Polar Pure. This method is field proven by hundreds of professionals over several decades all over the world (this is not "iodine tablets").