hi all been looking on this site for around 2 months now, great info from you all. Now with my question, i am running a 400w hps and just wondered how far from my plants i should keep it, i have read that it should be around 6 inches is this right? my plants are around 3 weeks old and havnt much growth on them since going in the room. just unsure how far away they should be as i dont want to burn them. thanks for your help
check with the back of your hand. Take your hand from the top of the canopy and raise it up toward the lights. At the point where it gets to hot to keep your hand there....your plants should be below that level
I got a 400w HPS myself, I like to keep it about a foot away from the top of the plants. If you have good cooling and air circulation, you can probably get it closer.