General Homebrew Discussion / Re: Change for the worse in Star San longevity? At least in my new bottle...« on: February 04, 2014, 06:57:46 PM »
Softened water (ion exchange as noted by Martin) with Star San stays good for me quite a while, but I have gone to changing it out after a week or two, just to be safe. I don't have any problem with that. I occasionally go with distilled, and keep it around longer in smaller quantities like a gallon.