another lighting question

okay i have plants growing at the mo but they are growing realllly slow. I was just wondering if any1 can tell me how much light i should be giving them from the beginning? I've been told that 12/12 when their sprouting but when should i change the lighting cycle??? Or should i not be giving them 12/12 yet?

just put them on 24/24 right away and keep em like that until you want to start sexing them.

cool thanks

Usually when they are in the growing stage, they should have 18 hours/day light and 6 hours in total darkness. When you're ready to flower them, switch to 12h/day light.