ditch the aluminum foil! it can cause hot spots. hence the flat white.

as far as the fans, exhaust goes up top. if hot air rises, then cool air must fall. and if the fans are exhausting air out of the top, in turn creating a neagative pressure in our box, then that negative pressure must be filled. so cool air is pulled in via our inakes.

if we exhausted out the bottom then the air coming in the top wouldn't be as cool as air lower to the bottom of the box. not to mention, this way would be pulling your lights hot air over the plants and then out the bottom.

also, depending on the size of your box and how many CFL you are using you will get pretty hot temps. i've read that CFLs actually run hotter than HID, it's just that the heat is dissepated from many more sources.

good growing!


-shake