ph is righ around 6, there is an oscillating fan in there, no I don't spray them in the light, I've only sprayed them twice, both times with some thrive alive B1 green, right when the light goes off, they always respond well to this.

How often can I foliar feed them? they always seem to perk up and grow really fast after I do this but I don't want to burn them with too much nutes.