even led lights do not just throw their light straight down. not covering the entire tank top with them might make you wish you had after they are all done and hanging. that being said you can also look at it from the point that a center brace blocks lighting pretty well regardless of the source. its one of those six of these half dozen of the other type answers. heat on the other hand could be an issue, make sure the lights are not so close they heat up and warp that brace over time.