The top is a bird netting from home Depot. CHEAP! It is perfect as it does not affect the amount of light passing through AT ALL! Squares are about 1" so tiny fish could get through. The eggcrate really cuts the lighting in my opinion and while I have not tried the metal eggcrate I think the thickness of it alone would be bothersome to me. Plus it would be tough with the salt I would think it will become corroded fairly quickly but...it would be easier than assembling the mesh top.
__________________
Red Coral Online Store
www.redcoralaquarium.net
45 Gallon Cube with 10 Gallon Sump, Lighting 8 bulb T5, Vertex IN 80 Skimmer
-2 Occelaris Clowns, Engineer Goby, RBTA, Peppermint Shrimp