you have 405w of CFL :thumbsup:

IF you were using incandescents, you would need 900w to equal the amount of light that you have now, which would easily drive tempertures way out of control and fry your plants... even if it were feasible, you would be more than doubling the cost in electricity

heat / electricity / lower light output are the 3 main reasons why incandescent lights suck, and shouldn't ever be used in a grow.

CFL lights can be had in the same and even better spectrums, there is no good reason to use incandescents over CFL.