With nothing but a picture, we can sit and guess. Soil/ Hydro? Temps? Nutes? pH? Auto/ photo? RO/Tap?
Yeah sorry, was in a bit of a rush yesterday when i posted this, wasnt thinking straight. Growing in coco/perlite, about 70 coco/ 30 perlite keeping ph at around 6 but not fixed on 6 as ive read its good to let ph fluctuate a little but i never stray more than 0,1 or 0,2 up or down really. Dont have a way of checking temp or humidity at the moment, but its definitely not very hot as im growing under cfls and i have decent ventilation and circulation, but its definitely not cold either. Sorry i know my observation on the temperature is stupid, and doesnt really mean anything but its the best i can do at the moment. Growing from bag seed (photo) using tap water, nutrients are bio-grow (8-2-6) for veg and bio-bloom (2-6-3.5) for flower, from a dutch company called bio-bizz (dont know if you would have heard of them) who make strictly organic nutrients (i have verry little knowledge on nutrients, but this is what was recomended to me at my local hydro shop), i am also using a cal/mag nitrate which also contains boron.