you can flower under T12s, get the Kitchen & Bath (red spectrum), BUT, your buds will tend to be light and fluffy - to get the dense tight buds, and good yield, you are better off with the HPS sodiums (like Stinky suggested) - BUT, if your budget is tight, the fluoros will suffice, until you get a sodium - I grew for 30 years under fluorescent tubes, gradually working up to 12 tubes - that's a lotta weight to move around - but, then, I finally switched to a 400 watt HPS, and it was a BIG improvement - :smokin: