As I understand it, this is your 10G. The black thing on the left is the skimmer, I take it, and the grey bar on the left is the input plumbing. The black thing on the right bottom is the return pump and the greay bar is the output plumbing. Please correct me if I'm wrong.
The problem with this simple layout is that you will get a lot of bubbles going back into the return pump. Bubbles rise, and all the bubbles that rise to the top will overflow into the pump return chamber. In addition, the cascading water will make bubbles of its own. So I recommend at least two more baffles to get this idea to work.
Also, consider what will happen when power goes out. The main tank will drain into your sump, so you have to make sure your sump can handle all that extra water in the event of a power outtage. With your design, it can only hold as much additional water as there is in the pump chamber. It might not be enough volume.
Here is what i would do with that design.
First, I lowered the height of the first baffle, this will give you more saftey room during power out.
second, I added the angled baffle on the right. As the water cascades over the center baffle, the bubbles will just roll around at the top, and bubble free water will go through the bottom.