second grow, some kinda deficiency...(with pics)

alright crew,
got 3 different strains going in tent...kc brains escape, the church and northern soul.
600w lighting, drip system using cyco a+b grow nutes, they seem to have no magnesium or manganese in them but im not too sure if this is my problem... the water cycle is 5 times daily into perlite/vermiculite mix...
they dont seem very unhappy, i just want to correct any problem before it gets out of hand and i start hammering my head against a wall.
i have attached a close up of one of the worst leaves i pulled off of the kc brains escape which seems to have the most yellowed leaves though it has proven itself as a wonderful low maintain. strain to me in the past...
im not too sure how long they have been growing for as i seem to lose track and just start to flower them when they look about ready to do so...which should be soon.






thanks guys.

anybody???? haha

u got some serious nute burn there man , i would flush and go Half the nutes of wat u were adding until u switch 12/12

for real? coz i just flushed for 7 days...its while i was flushing that the leaves started to discolour?

i also have only been using half of what the nutes say to add to my reservoir