The city would actually be pretty cool too and a better static pic as well.
I've been lurking for a couple years on this site and have recently (march) joined. I remembered seeing this thread somewhere and glad I've found it again now that I can more easily stalk it....lol
I went back a bit to jog the memory and saw the sump post question. Did you figure it out? I can tell you I used Rubber maid stock tanks for my sump system when I had salt. Best thing I ever did. I had two 55g barrels with filter socks to catch all the junk from my two reef tanks upstairs, those went to a 100g Rubber maid tank with a higher micron sock and a ton of live rock, this dumped into another 100g RM with a return and heaters, I fed my refugium 50g rm off the last RM with another pump and it sat above the final chamber, my skimmer was a beast and I spent a ton of money on it it was a bashsea twisted monstrosity it was fed from the live rock chamber.
I wouldn't use a wet dry too much salt creep generated. I am using a wet dry on my current set up but it's fresh water. I've left the addicition for now. Lol.
I put a few mods on the system after initial build, like drain valves on the bottom middle of the 55gs to get rid of any sediment easily. And I made some changes to the fuge to make it feed off gravity instead of a pump. I also installed a biopellet reactor.