I hate to say but your hydro guy is just plain WRONG. Yay for uninformed retail staff... :wtf:

5.5-6.5 is for HYDRO. 6.5-6.9 is for soil. REally get it up to the upper 6's. 6.5 is so on the edge that if you have acid rain in your area (Like upstate NY, PA, etc= really bad) there's no wiggle room.

I think tht if your other girlies have begun flowering on their own you are reasonably safe leaving the original ones on natural light to finish, especially since I imagine you brin gthem in during normal evening hours, correct?