Well, I didn't know if it was a brace or not, it's just a flimbsy piece of plastic. I figured it was a way for the manufacturer to save money because it allows them to use two smaller lights instead of one big one.
I'm using a single MH 400 Watt, 12-13 inches off the surface of the water and 2 T5 actinics. I get good light distribution, just wanne get rid of the shadow. I guess I'll have to find another way. LOL.