I see in this picture that some of your fixtures dont have reflectors. hehehe... you can almost double the light getting to the plants. Here's how to make a cheap hood for CFTs.
This
ONLY works for CFTs < 100W (total).
Other HID lights WILL cause fire hazards and hot spots!
Make sure there is NO exposed wiring on fixture!
Take a breakfast cereal, ritz cracker, or whatever cardboard box apart carefully at the glue lines. Flatten it out. You'll end up with a largish rectangle of cardboard thats about as wide as most rolls of aluminum foil. Roll the aluminum foil - dull side out (athough it doesn't really matter with CFTs) - over the cardboard. Crimp the foil over the ends and tape down. Cut a hole big enough to slide your electric cable - but not the fixture! - through right in the middle.
Bend into a semicircle, like a quonset hut, hangar, or corrugated metal building. Use duct tape to tape the sides together at the ends, and the middle. (I put CDs on the ends, as well) Slide your cable through the hole. Hang. Voilá!
The aluminum will act as a "heat sink" for the ballasts (the big white heavy non-light part) or the tubes if the hood happens to be sitting directly on them. There is
NO danger of the cardboard reaching ignition temperature. If a fire happens, it'd be due to other causes, not the cardboard catching on fire from resting on the light.
I also have several flat "panels" made this way that I used to use in the stepladder "growroom" during veg. The neat thing about CFTs is that "hot spots" are damn near imposible to get; you'd almost have to make a parabolic reflector and set the plant at the focus.