This is my first experience with hydroponics. At first my tomato plants took off and really grew well. I started getting some blossoms, pollinated with a toothbrush, and waited for fruit. Then one day my plant was covered in white flies. Got rid of the white flies, and a few weeks later my plants look like this and no more blooms. I've been following the schedule for Fox Farm's Grow Big and always keep my Ph between 6 and 6.5. Can anyone identify my issue by the sad look of my leaves?