In my opinion 24hrs of light is not efficient. Plants in veg need adark period just like during flowering. During the dark period the plant diverts it'senergy from veg production to root production. The stronger and heathier the roots the increase in potential there is for veg and flower growth. I've also read in a few booksthat a plant is unable to absorb more that 16 hoursof light a day and anything extra is wasted energy. I myself push this a little and use 18/6 for veg. But that's as far as I am I plan to start flowering with 12/12 the firsat ime this weekend.