looks like nutrient burn. especially if your ph is reading at 7, you dont have to treat your soil like its hydro and use ph up or down. a bit of dolomite will go a long way and keep you from screwing things up. a flush is a good thing, and i agree not to cut them off. i see no reason to be using anything other than the fox farm nutes once your girls have used up a bit of whats in the soil. the plants should have a good 1-3 months of growth in fox farm soil before any nutrients NEED to be added. you can use simple tap water, and let it sit out over night to let the chlorine evaporate. if youre set on using r/o then use the calmag as stated on the bottle. the rest of the stuff you have there is pretty much just gimmicky bs, my two cents at least.
What made you decide to pick out those specific items? if it was the people working the hydro store, looks like they just took you for a ride and tried to sell you anything they could.
if you saw their wholesale catalog you would sht yourself looking at the price mark ups.