I'm still struggling with my pH, which hovers around 8.2.
It is not the grow media because my second system has hydroton as grow media and the pH is the same.
I talked to a guy who runs an AP system a couple of blocks from me and he had the same problems and he said it is our water and only when he got a RO system he was able to control the pH.

Here my question:
I see a lot of RO's(typical kitchen, under sink ro's) on craigslist, is it possible to modify these units and hook them up to a graden hose for outside use? Water pressure might be an issue...but i'm ok if it takes a couple of days to fill a reserve tank and then pump it into the FT.
I don't want to invest in a hydroponic RO system made for this if i can get a used one for under 100 bucks.

thanks