The standard plastic hoods that come with tanks are only good for NO
florecents. If you added a VHO
bulb or a HO
bulb to the hood you wouldnt get the benifits of the increased light output potental. You would need to swap out the ballast with a ballast that was designed to drive the VHO
bulbs. By the time you do this you might as well purchase or build a new enclosure because the heat outputed by the higher output florecents will be enough to make the plastic hood nice and soft.