Ok. First, how many tubes are you using? Is it 2 fixtures containing multiple tubes, or just 2 tubes? For that size, you should have 2- 6tube (8 would be even better) fixtures plus side lighting. Side lighting could be CFLs. But if your current lights are a 2- tube fixture (or 2- 1tube fixtures) you could use them for sidelighting. Post back with your lighting info. Wouldnt want you to waster your seeds.