How many inch should cfl lights b away from plant ...

Hi @happytimes! I've been using a 200W CFL for a while and noticed this: you can indeed put the lamp right above the canopy, even as close as 2 inches / 5 cm, BUT it's all about the airflow. Concretely 2 inches won't burn your buds if the plant's summits does receive a slight continuous fresh breeze. Otherwise, if the air is static, a 2 inches plant<-->lamp distance will burn the apical summits. In other words, every setup is different, due to different bulbs / different fans / different environment temps. The best thing is to try by yourself, during a two days period where you can watch your plants every hour or so (weekend?): start by putting the CFL at 10 inches, check the heat with your hand and give the plant 3-4 hours to react. If she's showing curling-upward leaves or other heat-stress signs, increase the distance. If she's praying the light and don't seem to bother about the distance, decrease the distance a bit and give her another couple of hours to adapt & react. Doing this step by step, you should be able to determine the best plant<--->lamp distance for your setup/environment. Hope this will help, keep us up-to-date and happy growing 👊

Hello ! Agreed with @HighTV , this link can be helpful 👉 https://www.growweedeasy.com/cfls

hey happytimes, for CFL it's actually up to the heat - you don t want it to cook your bud, but you want it as close as possible : between 10 to 20 cm if you can. Hope this helps ! 🚀