I would veg them a little longer before going to 12/12 and let em get a little larger, maybe a foot tall before flowering. Look nice though. I would suggest a better soil than MG or anything MG for that matter, MG just isn't for these plants. Try some of the local grow stores for good soil and organic nutes. I was recommended bio bizz and that is some good stuff so far. Make sure the temps don't go over 80 degrees in the grow space, good call on the fan.