maybe just maybe the spots on youre weed is from the mirror effect whitch causes burrning , Thats why I was sayen no mirrors.The foam wall can be cut and formed then tape it with white tape (Its like ducktape) Go get a emergancy blanket they look like milar and you can see through it real well while the light is on. the styrofoam sheet is like 1/2 inch thick , you can even cut holes in it for your ventalation fan. Go to lows and go look at what im talking about. I thought the same thing untill my buddy showed me.