C
CannabisSativa
alright this is a classic, i forgot who had this thread up here, it doesn't matter bc i wouldn't reveal this anyway.....
so this guy "has a couple grows under his belt" and was asking about differences in lights
He bought a metal halide light and used it the entire grow excited about his new blue spectrum light
but his question was
I know my metal halide is a blue spectrum but do i ever have to replace this blue film on my reflector glass? And where can i buy red film for flowering?
This one wins. I was so intrigued that I did a search for "Blue film" and I think I found it LOL.