3 different kinds of hydroponics

I am growing in a closet that is 4ftx5ftx8ft tall. I am currently useing 4-40watt(each) florescent lights. I am testing out different types of systems to see which I get the better yeild and the stronger potentcy. I have 7 plants which all are females and all the same genetics. Each is about 5 inches tall. I just trimmed them at the beginning of this week. Sprouts have already shown growth. I have split the plants into three different systems: 1drip, 1bubbler, and 1ebb and flow. I do have a 400 watt HPS lamp but because of Paranoya I have chosen to use it only when necassary. A small fan is on the plants to strengthen their stems. The plants so far have only run into one complication which was chemical burn but I have taken precautions and have corrected the problem. So far the roots in the bubbler have grown the longest and as well the stems. The drip system has the greenest and widest fan spread. Where as the ebb and flow have the strongest stems. The complication I have run into are about the lights I have left them on 24 hours until now I recently changed the lighting schedule to 16 on and 8 off. Which caused all the leaves to droop down. After giving the plants about a week and a half to recooperate back to original status I tried 20 on and 4 off ,but the same thing happened. They are now back to original healthy status. Should I just leave the lights on 24 until I change over to my HPS. Any suggestions on anything will be appreciated.