Had them on 12/12 to early, now what?

I put my plants on 12/12 light early in their lives, they have grown up decent and are now about two feet tall, what lighting should I set them on the get them to start flowering?

Also I am having some problems with the bottom leaves getting spotty, then withering and falling off (Only at the bottom). Also I have these guys side by side, four of them each in a three gallon bucket, should I move them two to a closet? I read that having them close together cam stunt the growth?

Thanks, and happy smoking!

as long as the new growth isnt discolouring it should be ok i looks like nute burn but not for sure and the lighting should be if using cfls use the 2200 lumen i believe its called day light? or a hps

Its MAG def .... Do u use soil or hydro?
U can use cal/mag or epsom salt