Very nice reef.
My only small concern is the wire splices you put in for the fan being exposed. Even with it on the outside it is subjected to humidity which will make the metal connections inside rust. I would wrap those with some electrical tape at the very minimum. Ideally you would solder the wires together and use some wire shrink wrap to seal it. Very minor detail though. Also, probably temporary, but duct tape doesn't usually last long in an aquarium setting, but it looks like the fan on top is on the outside and no risk of falling in the tank if the tape lets go.
Again, tank looks awesome!