I have seen leaves come back to green that have looked worse.
How did the discoloration originate ?
I would not increase food until I see signs of nitrogen def. that doesn't look like it.
I would run clones 10-15 % strength. Not sure what your 25% is.
I have had great sucess in hydro, with very agressive feeding and the Lucas method.
Environment , ( res temp, ambient temp) is paramount.
I would be concerned with your space shuttle heat Shields trapping heat in the bucket