enough lights?

right now i've got two 48in flouro tubes each pushin about 3400 lumens. is this enough for 2/3 plants? i've also got 2 more 48in. tubes that will produce like 2400 lumens each, but i would have to get another ballast or whatever it's called you put them in.

For early growth that lighting setup would work fine, but when you plants start getting big they will need a lot more light. If you could get another 2 tubes going that would be best.

so probably the 2 lights i got goin now then switch to 4 when i start flowering? and how many plants you think i get get out of it, i'm startin 4 just to better my chances of a female, but i'm sure i have the room for 3