Something like this?
On this sump flow is right to left
with the bells and whistles - effluent cup with holder for PH probe, heater racks, filter socks and bubble trap before the return, adjustable ATO , buddy uses a Hammer-Head for a return pump :squigglemouth:
Couple of things to remember:
1. Don't make your baffles too high, ie for a 16" tall sump the highest baffle should be no more than 10" (first baffle)
2. Figure out how much water you have when the return pump goes off (see #1)
3. The only place that the bubble trap is needed is before the return pump and even then sometimes a two baffle set-up can replace a three baffle set-up (room)
I normally use 3/8" for all my sump builds but if it has to span more than 24" then 1/2" thick material will be needed (for the bow), always use a euro brace of some sort (for the bow)
my sump showing the return area, bubble trap and the manifold to feed my calcium reactor, Phosban and carbon reactor that return is a Reeflo 3600 and no bubbles in the DT, heater racks and adjustable ATO