Usually the plant stretch the first 3 week when flip to 12/12, in these 3 weeks you can see them grow 1 inch per day and even more. In you're case at day 28 you should not have any problem. Checking the FAQ's you can see the chart : Flourescents: proximimty, 400w HPS: 1 foot, 600w HPS: 1.5 foot, 1000w HPS: 2 foot. So any lamps less than 400w 6 inch should be perfect.
LuciferN Reviewed by LuciferN on . Not my first grow but first grow log! Indoor grow cab (converted Home depot wardrobe) 4 pots, two left over KC-36 and two Dutch Passion Oasis Makeshift growlight - featuring a 125 watt CFL (rated 5000k) with an aluminum turkey pan reflector one bottom fan (and digital thermometer) blowing cool bottom air at the pots One top fan 'sucking' the warm air up average cab temperature 27 Celsius After 3 days of sprouting only one seedling (one of the KC 36's) popped out of the soil (I did presoak the seeds for 12 hours) on Aug 5th Rating: 5