hydroponic gardens

[Michael]

Hi Ron, I am a novice at this and my results are varied. I'm using a commercial two step nutrient solution in a drip system with perlite and metal halide lights My tomato plants do well until they start to flower, and then the leaves start to turn yellow and curl up, sometimes with brown spots. I thought they were getting too much water so cut back to 2x a day, but from what I read, most other hydroponic gardens get watered much more often. Drainage does not seem to be a problem, but my roots did look somewhat brown last time I pulled a plant...Any suggestions?