Flouro? or what type? Mine are under about 75 watts of flouro and are doing fine. I have 3 small plants about 5 or 6" i think and are still in veg.
75 watt flouro will do alright while they veg, but you're going to need more during the flowering stage. A 75 watt incandescent is almost worthless.
I grew one plant under a 70 watt micgro-sun combo cfl/hps lighting system in and had great results, it can be done good luck.