i would think you would be fine omitting the center brace if that's what you wanted to do , i have no brace in the middle of mine on the back side , tank is 5' long , but i did use 2x6 for my header across the top . it looks like you have double 2x4 across the top on a 4' span with no concentrated weight in the middle you would be fine , again if that's what you were hoping to do .
-Russ
|