i have a 55 with a 2X55 bright kit from AHS. with this amount of light should i be adding pressurized co2 or would i need to get another 2X55 to really see the results? also what about ferts, i use excel now but was reading on rex's site about his dry ferts. would they be the same dose with 2 wpg as 4 wpg. sorry if i confused ya - thanks for the help