t12 daylight bulbs rock, i have a couple and they keep the height of my plants really low which is cool for LST or FIMming.
My t12's put out like 1600 lumens of blue light spectrum per tube.
good for veg growth.

And the plants won't burn if they touch the tubes, that's always nice.

t12's are big so that's why people suggest t5's, so you can fit more of them into smaller spaces.

My tubes are cool to a touch keeps my temps real low/ I'm currently trying them with a combination of CFL's. The CFL's just toss off so much more heat. Pretty good on the electric bill too.
Dyranty Reviewed by Dyranty on . Question on T12 (floresence) Hey everybody, Its Haro Bmx 420 again, was just wondering if anyone has input on the T12's rather then the T5's. The T12's are bigger and give off more lumens to my knowlage and have like no heat and higher wattage, im just wondering if T12's are as effiect why or why not? Rating: 5