Wow great thread. Lots of good DIY info. I'll post mine, sorry I dont have any really good pics yet of the whole thing, just bits n pieces.
240G display tank, twin 33G tote sumps plumbed into a single return pump.
BTW there is no wet/dry part since I inject CO2, entire sump is flooded.
I run two DIY filter boxes on the pump intake in each sump. they have about 1 sq ft intake area with filter floss, and maybe about 2 gallon volume of potscrubbers for bio media 9they arent completely full in the pics either, ran short). Total of 4 of these on the tank.
Silencer module I built. The drain comes into the side of the top wye which is at water level, water goes down and air bubbles go up (tiny vent hole drilled into top of cap). The bottom Y is actually sealed on the base (not visible in pic) and all the flow comes out the side through a fine media bag (catches coarse material, fish, shrimp, etc.).
I also insulated the sump tanks all around to try and minimize heat loss, but I have so much stuff now running into and out that I have not put the lids on so not sure how much good the insulation is doing.
Return pump is a Sequence Dart. I'll try to get some better pics showing everything more clearly...
Also pretty much everything is / will be automated, water change, co2, fertilizer dosing, etc.