i am having the same problems right now.
Flower: 6x4x8 room, 2 600 w hps, carbon filter w/ 6" duct, ocean forest soil, fox farm nutes plus silicate, zyme, bud candy, mc/cal, ph 6.5, plants are 2.5 ft tall.
Veg: 4x5x7 room, 1 400w MH, carbon filter w/ 4" duct, same with all nutes, ph 6.5...