Stealth 2.0

how would 6.8ph water cause ph issues? it was fine with 2.0 ec through veg but it started burning the plant once it started flowering because they get more sensitive to overfertilization during flower then they were in veg and they are overfertilized as evidenced by the tip burn and the claw. that yellowing inbetween the veins is more likely a magnesium issue than ph as 6.8 is a good ph for soil. i’m suspecting he still has nutrients in the grow medium so i’m gonna suggest plain water for a week then feed with 1.0 ec with appropriate nutrients (grow, bloom, micro)