Nutrient Def.? Someone has to know!

Hello

First time grower, first time poster. Please forgive ignorance. Ok. So I vegged for roughly 4 weeks and then moved to 12/12. I did not do this when I saw pre-flowers because I wasn't aware of that being the indicator. Instead I moved them when space became an issue and perhaps I was too excited. They are clones so I am not worried about hermies. Everything is going really well, plants are huge 2 weeks into 12/12, however, there looks to be either a (N) or (P) def. I am using Jorge Cervantes' book and believe it is (N). Picks are attached. Another problem is that only one plant seems to be showing significant signs of pre-flowers. That one plant has one pre-flower with undeniable pistols. I am nervous for the way my leaves look and also for the very slow pre-flower development. I know time can tell, but maybe you can too. My grow box is hot, there is no question, but after this harvest I will be severely upgrading my setup. I have also raised the light, (600hps/400hps), in fear that too much light might be causing the canopy to be lighter almost yellowish. THoughts?

WHen I say hot I mean upper 80's around the lights, AC ducting running 76 degree air into the bottom of the box

looks like a zinc def. whats your ph at? what its your water ppm. it might be a lock out. quick questions. soil or hydro? nutes? water source? a lock out could cause slow growth and nute burn when trying to feed it more nutes to compensate for a defincie.

I am using biothrive bloom with those plants. I am using soil. I don't know the ph or ppm of the water, I need to get the stuff to test for that. How do I combat a lock out?

grab distilled water from cvs or walgreens and flush it, if it starts to look better after after a regular watering or 2 it was locked. but if it looks like its getting worse after a flush and some nutes just add some cal mag lightly and it should work. let me know if anything works. hope it does.

Alright, I have not flushed yet. I have not watered again yet. My leaves are not drooping and its been a day with not water, which leads me to believe that I been over watering with ferted water everyday and that I may have induced chemical burn (my ferts are organic so I don't know if thats the right term.) I also dont know the PH of my water yet or the ppm, I plan to visit the local grow shop tomorrow to procure the necessary equipment to get those readings and adjust accordingly. I have been watering everyday, with roughly 4gal between 12 plants. So from the pictures, you can see that the tops of the plants are almost all yellow, and the bottoms are still mostly green. Leaves are beginning to die and I don't want to loose everything. I need advice and I need to act quickly on it (meaning tomorrow). Unless it seems that a flush is necessary, in which case I will do it tonight. Thoughts? Thanks.