What do you think the problem is?! Help!

Please help diagnose the problem with my ladies!
This seems like a serious problem... any help would be great.

How long has this problem been going on? - Less than a week.
Are you growing in a PVC grow tent? - yes. a no name 4x4x7' tent
What system are you running? - Ebb Flow
What STRAIN are you growing? - Platinum Kush
What was the establishing technique?- Clone
What is the age of your plants? - 7 weeks
How long have they been in there mixture they are in now? - Sure To Grow medium for entire life.
How tall are the plants? - 2 feet tall
What PHASE are the plants in? - Flower (for less than a week)
What Technique are you using? - n/a
What substrate/medium are you using? - STG Sure To Grow
What is the Water temperature?
What color are your roots? - cant really see them, but they are growing out of the holes in the bottom bucket. Seems white.
How much of each nutrient are you using with how much water? - Im using Sensi Grow by Advanced Nutrients. 6 tablespoons of each part a and part b.
How often are you feeding? - I top off the water with nute mix every week.
How often are you giving nutrients? - 1/wk
If flowering, when did you switch over to using Bloom nutrients?
What order are you mixing your nutrients? - Silica grow, part a, part b, organic compost
What is the TDS/EC/PPM you are using? - 900ppm
What is the pH of the "Tank"? - 6.5
Are you sure your calibration is correct on your equiptment?
When was your last watering? - 2 days ago
What is your water temps? - n/a
When was your last feeding change? (ie. grow-bloom-micro-additional)
How often do you clean your system: example: Flush out water replace with clean water and nutrients? - every month
What size bulb are you using? - 600w hortilux
What is the distance to the canopy? 2 feet
What is your RH Factor(Relative Humidity)?
What is the canopy temperature? - n/a
What is the Day/Night Temp? (Include flucutaion range)
What is the current Air Flow? (cfm etc.)
Tell us about your ventilation, intake exhaust and when its running and not running ?
Is the fan blowing directly at plants? - almost, but not quite
Is your water HARD or SOFT?
What water are you using? Reverse Osmosis and tap
Are you using water from a water softener? - no
Has plant been recently pruned, cloned off of or pinched - 2 weeks ago
Have any pest chemicals been used? - 1600x pyrethrum and Floromite
Are plant's infected with pest's - yes mites

NO ONE?! nothing? woww.. way to go rollitup.

Anyways for others who have this problem, Ive been getting feedback that its either heat stress, or from a ph imbalance.

Some were suggesting that it was off-gassing from my tent, but that isnt the case. I will post something as soon as I find out what the exact problem is. seems like no one is sure of whats wrong with it.

Ill stop talking to myself now.

is that a homemade or cap ebb and grow? it appears you have nute lockouts, the first one is N, but also maybe IRON, also that top looks like severe light bleaching, how close are the lights? i have heard from a member of another forum that STG inserts for the buckets wrecked his crop in a similar system, all was well till he hit 2 weeks flowering, im sure you have a small pool of water under each bucket inside, try raising the buckets 1 inch, even STG makers on youtube say to raise the insert so it dont rest in the water, makers of the cap system say if plants arent looking healthy to do this aswell, if its a healthy root system filling the bottom bucket it should take it up no problems, but you could have a major build up down there, flush with plant water, this system flushing isnt easy, since the flood cycles are 3-4 hrs you should give plain water first day and change water out again, total 3 day flush, 1 day flush does nothings since tons of salts get built up in the connecting lines, after wseeing what this dude went thru with these inserts i would never try them, stay with hydroton, its a pain but best media for this