pure power plant issuse

hi there, iam growing pure power plant.
i am in week 5 (end of it)
the plants grow in soiless mix and the nutrients are Plagron (minerals)

check out the pictures of the plants and tell me what u think.

p.h is 6.2-6.5
PPM is 780
adding bloom and green sensation.
the ppm was 1200 and i lowered the food the plants.

you can see as well the flowers, one of them got to be brown and white like the others.....

no one can help here?

i cant say i really see a prob. the leaves tend to do that toward the end of flowering, it uses all the nutes left. but keep an eye on it
( i have seen worse)