Can I Turn Lights to 12/12?

[Dan K.]

i got about 15-20 in. of grow space. what is more recommended? LST or Toping?

also i read up on LST but a few questions. are my Side leafs goin to turn into the main steam(s) and do the zig zag and is this goin to double the amount of time for veging?

What does 15-20in. mean?? Height?? Width?? Length?? If you only have that much height and your plant is already a foot tall, I would LST immediately and then probably switch to 12/12 to avoid running out of room.