I moved the port cichlid into the 80, which completely relieved all of the cichlid tension in the tank. I also managed to brace the wood that was sticking up out of the water down so that no wood is within about 3" of the waterline now, thanks for that info lyzheng. The two side pieces are in the tank because they still float and are still leaching, I plan on putting them in the 340 along with another big piece that I just threw into the 80 to provide cover for the port cichlid.
To lighten the tone a bit, for the people worried about the safety of the fish, the oscar and the severum are really docile when the port cichlid is out of the tank. They pass by each other without any sort of signalling or anything. Neither of them really like it at the top of the tank, they hang out at least 6 inches down, usually by some desirable feature in the wood. Nothing hangs out at the top of the tank.
The top of the tank really isn't a big-fish-friendly zone. It's difficult for them to move around up there. The only time one of them goes up is when the clown knife gulps air, and he only really has room to do it in one place.
My granulosus is SMALL. All 3 of the catfish and the clown knife could eat it, but none of them have ever eaten live food, just pellets, prawns, krill and beef heart. None of the fish display any aggressive attitude towards it at all, they even let it munch on their sides like a remora. The tiger shovelnose and the clown knife in particular have had the opportunity to eat many small fish including a couple earth eaters, the granulosus, the port cichlid, and a 5" pike(which by my estimation will be smaller than the aro I receive Wednesday morning). I hope to never have to house the aro with the bichir, but it's also had many opportunities to eat fish smaller than this aro will be, including the port cichlid presently.