I use Star-san exclusively. My friend uses the iodine-based one Amberdyne. They are both touted to be no-rinse
solutions and we treat them as so.
All of my friends beers have a common taste element to them (ALL beers, Scottish, IPAs, Belgians, etc). Just a hint, but it is always there. My beers do not have that taste. After effectively eliminating water as the culprit (at least seeing that the PH of his home water is okay), I'm starting to question his sanitizer. Is that possible?
Also, he said after just a day or 2 he gets a film on top of his sanitizing solution and he has to make a new batch. I keep mine for sometimes 2 weeks and it seems fine. How long CAN you keep Star-San? I have heard that it will become cloudy as it loses its effectiveness, but have never pushed the envelope past 2 weeks.