Fast growing skunk #1

I have a cupboard thats 1200mm wide x 700m deep x 1500mm of growing height. Its designed for two plants each in a 400mm pot, running a recycle hydroponic system using 'Hydroton' clay balls. I use a 400w Son t agro light. Has two fans, one high speed wall fan situated at the base of the cupboard and a econo toilet fan directly above the light. Temperature ranges from 19.8*C at when the lights off and up to 29.3*C when its on.

I have used what I thought were two Skunk #1 seeds. They are now 3 weeks from germination. They are massive. One already stands at 9in in height with a fan leaf width of 14in. This one is definately Skunk it smell strong already. Almost pure indica. However my other baby looks like it has more sativa in it. It is taller (about10.5in) but only has a width of 7 inches. It has skunky looking leaves but the way its growing makes me think its something else or possibly male. Either way they a both awesome looking plants and I'm stoked with the progress.
I started the seedlings on 1/4 strength vegetate Hydro nutes. They are now on full strength.

Can anyone reccomend what height I should start flowering them at

if your really worried about it just grow 12/12 the whole time
im to lazy to crunch the math but in gernal plants double in hieght when they flower do take the left over space after your pot is in there devide it by 2 that will give you your height when to flower

I didn't think it would bud if you grew it on 12/12 the whole time. I currently have it on 16 /8 and was going to reduce it to 12/12 when I want them to flower. I'll give it another week.

Skunk#1 is my favorite strain, it is mostly a sativa with a little indica so when you flower it, it will stretch a bit about a 1/3 or so. why do you have it on 16/8?

accendently started on that instead of 18/6

stupid analog timers