so i'm trying to figure out what to do with the readings that i've taken of my runoff water in my plant. what is the ideal ppm's and pH of the water runoff growing in soil? i've seen people say that 'you need to check it' but what am i checking for? currently, the pH of my runoff is 6.7-6.9 (i'm using 7.0 RO water) and the ppm's are ~330ppm. i'm guessing the pH is good, since the soil would be slightly more acidic than the actual runoff (using logic, i could be wrong?) but i have no idea if the ppm's are too high/low, good/bad. some guidance would be greatly appreciated. thanks!