i got a soil ph meter. it always wants to read about 6.8 it almost seems like this ph meter was a waste of a purchase. im using ffof with big bloom, grow big, and tiger bloom. i use them as directed except a bit less than normal so i dont burn them. i use RO water. i know they say like 6.2 - 6.8 for soil. should i lower it a tad and if so whats the best way? can i ad a little vinegar or lemon juice to the next watering? i dont want to do anything to fuck it up since they are doing awesome but wouldnt it be better to have a ph closer to the middle of whats recommended rather than borderline too basic?