Light is a huge factor. What kelvin were the flouros you were using? for that many plants you would need more than 4 of those i'm sure. Also do you know the lumen output? I found out the hard way that color-temp and amount of light that the plant receives is crucial in vegging. Just check out my journal i got some fucktards for plants. but i've learned so much from it i'm sure my next grow will be great. I just want to finish this one!!!
Maybe just step up the lighting, use your tubes for side lighting (will improve your foliage at the middle of the plant) and get some CFL's for the top. Or say fuck it and get a HPS and a MH conversion bulb and rock out!
Either way i'd use the tubes for side lighting.
Best of luck to you my friend, i'll be watching!