you should make some reflectors for those cfl's
get yourself some small plastic "shoeboxes"
carefully line the inside of them with the mylar, try to get it as flat as possible.
flip em upside down and cut hole out of the bottom that are the same size as your light fixtures.
voila! reflectors!
also you might want to move those tubes closer to your plants, they're not really adding much to the lumens on the plants.