Which sump design is better for flow?

[George]

A sump, like a display tank, is the bigger, the better. A few comments.
1. Why do you think you need more flow in your refugium? How much flow do you have for your fuge now?
2. You may want to re-size your partitions to give your fuge more space. Depends on what skimmer you have, you don't need that much space for skimmer section. Size your return section accordingly so you can have one week of evaporation water in that section (or how many days you feel comfortable), and of course can hold your return pump.
3. you don't need 3 baffles for fuge divider. The flow in the fuge is very slow and won't have that many bubbles. That design of baffles is for eliminating of bubbles.
4. Space between baffles can be as little as 1". Don't space them out too much. You are losing valuable space in the sump.
5. There is a red line between skimmer section and the fuge. Is that your fuge water feed? How are you doing that? Split the drain or a separate pump? Many people just split the return and add a valve to control the flow in their fuge.