Ok, as promised here are more pictures.
The previously seen brown painted walls are the outside of the acrylic tank. The tank measures 1.25 inches thick and is currently filled with water with no leaks. There are 3 main returns back to the sump tank. One 2 inch pipe feeds the overflow weir closest to the sump. There are 2 more overflow weirs in the tank, one in the middle and one at the other corner. The second 2 inch pipe drains the other 2 weirs.
A modular sump system could be contrived to fit under the tank in sections connected by pipe. The sump could handle your bio, and a couple of canisters to handle your mechanical. At 5 feet tall, such a tank presents both challenges and opportunities. It would make for a very impressive paludarium.
This is the middle overflow weir pictured above the rock.
Each overflow weir has 3 bulkheads at the bottom. One is attached to the 2 inch return pipe.
The other two bulkheads attach to smaller pipes leading back to the sump tank.
The 2 smaller pipes join back under the main return pipe and run back to the sump tank. This smaller pipe currently dead ends at a closed valve and simply communicates with each overflow weir box right now. It could easily be plumbed as a third pipe to the sump tank.
Another shot under the tank. There are multiple outlets wired under here.
A shot of the main area under the tank. There is plenty of space under the tank for a large sump tank but the support beams plus the pvc drain pipes block the path of anything reasonable in size.
This is a shot of the return pipe back into the aquarium. The 1.5 inch pipe empties water back into the aquarium at these smaller tubes scattered around the top of the aquarium. There is currently only one return pipe back to the aquarium.
A shot of the inside of the tank from above.
The return tubes are spread throughout the 3 sides of the aquarium.
