DE 315W CMH: Height & Dimming
Posted 14 April 2019 - 06:25 PM
Posted 15 April 2019 - 05:20 PM
I'm using a Dual 315W CMH unit. Unit does not have a dimmer.
My lights are set up for the moment at 750mm above the babies and have been since they broke ground. They have their 4th set of true leaves coming out strong(will be topping them in a few days). No signs of leaf burn or heat stress in the 4 plants. I can feel sweet FA heat at plant tops. At flower time the light is 600mm above SCROG.
Mind you, I have 2 fixed 6" fans blowing(24/7) across the plant tops and there is also a fan pushing and pulling(24/7) 420CFM of air in the 1.2 X 1.2 X 1.8M tent. The whole thing runs that cool I had to put 4X aquarium heaters in the DWC buckets to keep the nute solution at constant 18C.
Sounds like your light is too far away and too dim.
Posted 16 April 2019 - 04:26 PM
All good, as long as you have sufficient air flow and everything is cool(your light produces less heat than mine) inside your tent, you should be fine.
When the babies get a bit larger, you can consider dropping the light to 600mm and observe for a few days for adverse effects. If it works out fine, then rock and roll.