Aurora Indica with problems/curling leaves

im currently working on a AI grow and at three and a half wks flower
I cant help but notice overnight some upper leaves started to curl AGAIN!
This problem persists,cant figure out why.I know it spreads and i know itkills because Ive lost a previous crop to it.

DWC 3 gal
rockwool cubes presoaked
Ionic bloom 4tblp per 6 liters
Ionic boost 1/2 tbsp per 6 litersi
water temp.72-75 Ph5.8-6.2
closet temp.82
humidity 40-60- Im guessing
double outlet air line-4in stone
water source-aged tap adjusted down from 7.0 to5.8
250w HPS 12-18 inches above
fan blowing across tops
no need to vent (open closet in dark basement)[attachment=o224968]

[attachment=o224969]:hippy:

from first glance, i would say that your pH is a little high. you want between 5.3-5.8 for hydro, if i'm not mistaken.

you might also want to fill out the troubleshooting form in my sig.


-shake

I cant cut and paste too well but Ive answered the questions.
250w HPS 12 in from tops with fan blowing over tops.
Enclosed reflector
Good air supply
6 in net pots of rockwool cubes (Deep Water Culture):hippy:
Grown from seed
Tap water adj to 5.8
Check with drops
Adjust with mad farmer Ph down
Ionic bloom 3-2-6
Ionic boost 5-6
I change res when Ive replaced half of the original with topoffs
usally weekly ( she feeding rapidly)I topoff daily at least 11/2 liters usally.
4 tbsp per 6 liters bloom
1/2 tbsp boost per 6 liters
Ph flucuates daily from 5.8 to as high as 7
and I adjust every morning with the topoff usally incrementally
if I have to make a big adjustment
I never foliar feed
Open 2x6x8 closet
Day temp 82 / night temp 70
Humidy somewher between 40 - 60 %