300w Duel CFL for veg

I have a 300W gaint duel spec cfl which i wanna use for veg.

I wanna do maybe 3 plants but not sure yet. Im wanting to grow the clones for my veg/flowering room. it holds 20 plants doing a scrog.

just need to know if i need more watts, heat is a issue cant use hps in mother plant room and what number of clones to expect form 3 plants in say 9-11 weeks.

Thanks