48 inch sump build advice

[Bigreeflittlefish]

Hey all, building a 48L 20W 18H. Using 1/4 inch acrylic I’ll be running a 5 inch sock and eventually removing the sock and using a fleece roller which will end up in the second chamber:
My general question is going to be about the return pump section for the water baffles their both 9 inches tall i was thinking of having a 3 inch space between the walls roughly 3.5 inches over lap what do you guys think would think be enough to run quietly

 

[lapin]

Should work
I used the Blue what bulk reef supply calls aqua mesh.

 

[Bigreeflittlefish]

Should work
I used the Blue what bulk reef supply calls aqua mesh.

Sweet looking sump

 

[Bigreeflittlefish]

Do you guys think i should edit the lay out maybe add a sand / rock section for pod growth?