retarded growth on leaves and discolor

first 4 pics show retarded growth... at first i thought it was a bug or somthing so i looked and i made sure there is no bugs... so next im thinking somthing is wrong with my nutes in my system...

then while i was looking today i noticed a little discoloring on a few leaves and some bending of the leafs..

can some one help me find out what the problem is?? my first guess is to much Nitrogen

there are a few pics of the roots and of the plants.

little info on my setup...
in a small cab that is 30ix19x34
two 100w hps bulbs... with some supplemental light from a 15w 18 inch aquarium light that is blue and red...
i have lots of exhaust and negative pressure... (it will close the doors of the cab is i leave it almost closed)
temps are running around 83-91 during day and 78-85 at night.. (ambient room temp is always high during day)
Running it in a DWC system i made...
ph keeps fluctuating it was 6.5 so i added ph down and got it to 5.4 then i checked at night and its now 7.5 so i lowered it to 5.5 again... ppm is around 500-600 ... (it was at 1700 last week cuz i didnt have a ppm meter) but the pics are of new growth tho so its not from that....
nutes i have in tank... (when label said 2tsp per gal i only put in 2 tsp in the res of 5 gal)
- Foxfarm
- grow big (6-4-4)
- tiger bloom(2-8-4)

- Botanicare
- pure blen pro grow (3-2-4)
- Liquid Karma (.1-.1-.5)
- Sweet
- Cal-Mag
- Superthrive

change the res
ur flucuation and high ppm is/was probably the cause of ur problems