it depends on how u grow it. r u going to scog it. And no matter what they say 42watt cfl is not = to 150HPS. you should at least get enought clfs to =100
42watt+42watt=84 i would use 3 of them but for the price 23watt are alot chepper but u would nee 5 of them or 18watt and use 8 of them and so on.
And 27000 is not lums its the color spec.