I made one that is quite similar out of Acrylic.
You can do several different things to control the flow through the Fuge. You can T off the overflow and have some of the water entering the Fuge section and control the flow using a valve.
Or if you want an easier way to reduce the flow through the Fuge you can make the teeth a little higher on the baffles, entering the Fuge compared to the teeth of the baffles entering the return area. This will result in most of the water going directly from the skimmer into the return area.
HTH