Overflow box height, need opinions please

[Scotty LaBeouf]

So as you can tell the top of the box is about 5/8 below the top of the glass, This is a rimless tank will this be too high? how much water height flows over the edge usually, 1/8" or 1/4"?

 

[Pepcrylic]

The height of the water flowing over the wall will depend on the size of the pump used as a return pump. IMO I would have left a min of 1'' on a rimless tank.