I used to think that distilled was the way to go so I could "control" what my plants were intaking, but after reading what a lot of the "old-timers" were saying I made the switch to tap. Could not be happier. Saves me money and my plants r tons healthier. As far as using only potting mixes as ur nutes I have a question. Do u transplant during flower? If so does the boost in N that ffof provides not slow down the flowering process? I believe that u know ur shit and love reading ur post. I've always had this question tho. Personally I use the ff line of nutes (liquids) but I watch my plants. My last batch did not take to nutes very well so they pretty much only got molasses, but the og cross i'm growing now is a nute whore. I guess if u have strains respond to the way u grow then great. I just think it is really a plant by plant kind of thing. I also think a lot of the problems that we r seeing is a product of laziness. Seems like no one reads anymore.