This sounds much more effective and aesthetically attractive.Not sure if you have access to the back of the tank or how much room you have. But I've ran a fiji cube hang on the back refugium and it worked like a charm. Still have it just in case I do another small tank.
To OP, the member who left the comment might do it differently, but if its the nutrient export you're aimjng for, one way is to just connect the two the same way you would a chiller. Connect a silicon hose to a pump in each tank and the water will flow between each. That's the absolute simplest way I can think of off the top of my head.