Qdog, I wasn't aware about that with Chlorox, great to know, thanks. Danbo, I, too, like to use boiling water where I can, but sometimes it's unavoidable and I have to use chemicals (in addition, I'm planning for a commercial farm and creamery, and it's very difficult to get inspectors to go along with any regime that isn't soaked with chemicals, so there's that). I'm with Qdog - Star-San is awesome. I also like One Step, a percarbonate cleaner and, to some extent, sanitizer.
One the shelf life of prepared Star-San, so long as the prepared solution is kept in an airtight container, the anecdotal word is you've got quite a bit of time there. I believe so long as the pH remains at 3.0 or below, something like that, you've got an active solution (I can't recall where I've seen this...I believe a "clear" v. "cloudy" solution is also indicative of potency. Sorry, can't recall where I saw this, a quick look on the 5-Star Chem site doesn't discuss this. Google around, should be some better info). I've kept mine going this way in 5 gallon buckets for a couple of months or better. Never an issue.
Edit: Just found
this. Scroll down. The podcast given by the Star-San inventor one member refers to is no longer up, but this squares with what I read elsewhere. Apparently the pH threshold is 3.5, and the key is to use distilled water, as minerals can screw things up.