I think it is important to use clean water.....filtered or distilled or spring water that you feel good about.
I have an RO filter so I know most of the fluoride is gone, I don't think I would use filtered water that has just benn carbon filtered, because it won't touch the fluoride.
I used organic coffee initially and it was fine with me.
Then I bought SAWilsons and now I am using coffee from:
I am not sure if the palate of my colon/liver is refined enough yet to make any comparisons yet.....ha ha ha!!!!
but I would use the regular organic again.
I actually called the Gerson institute last year and asked some questions about their program and they told me they used to use SAWilsons and now they use plain organic coffee....