Instead of fluorescent bulbs why not use Cold Cathode light ? This is what I am using on my 240 gallon project. Cheap, simple to wire, and well cold... No heat build up. If not then no you do not need vents. I built a hood for my 20 gallon tank, and I just stripped a aquarium hood light and screwed it into the hood. No crazy heat, Only problem is that it warped the wood a little, barely noticable.
See the 20 gallon build in my sig line for an idea.
Good Luck
See the 20 gallon build in my sig line for an idea.
Good Luck