Well topping them will increase your yield, by keeping them short and bushy.

I top all my plants, or attempt to FIM (Grow Marijuana FAQ, Cannabis cultivation - marijuana growing tips & photos) them

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Grow Marijuana FAQ, Cannabis cultivation - marijuana growing tips & photos
Grow Marijuana FAQ, Cannabis cultivation - marijuana growing tips & photos

Because your plants only been in 12/12 one day it should be fine to reveg, but be quick.

How old are your plants? they should be at least 6 weeks old before flowering if grown from seed.

Your plants can double in size during flowering so you should flower them when they half the height you want them too be at harvest.

So if your plants are like 4 weeks old then yes reveg and top once or twice, or attemp a FIM.

Up too you

p.s Yeah i helped pretty damn quick but you were just lucky i was online, normally it takes a while to get posts, if you get posts at all

Peace :rastasmoke: