I use two different light cycles for vegging, an 18hrhr/on 6/off and a 12-1 cycle which is, 12hr/on, then 5.5hr off, then 1hr/on then 5.5off, then just repeat the cycle.
The 1 hour on in between the 5.5 hr off period fools the plants and they stay in the veg stage!
Best of luck bro.