Use glass over the center 2/3s of the tank and fit eggcrate over the rest. works realy well as long as you clean the glass atleast once a week, micro fiber cloths work realy good at this. wash with water and viniger then then rinse with water and this is where you use a micro fiber cloth. works well for me. figured this one out because I have a 5 foot tank and only a four foot light. This way air circulates still because both ends are open you don't even get much condensation happening.

Bill