This DIY is worth bringing back up once in a while. It's been a long time since anyone has posted anything here, so I'll move it to the top with a bad cell phone pic of the Wasser-Controller I recently built:
It's not pretty, but it doesn't really have to be. It works great, and should (hopefully) power everything I need for two aquarium racks.
I made two power stations that I can plug into separate wall sockets (separate breakers) next to each rack. I liked the CAT5 disconnects discussed in this thread, but decided to use thermostat wire and DMX plugs on this build.
Thanks for this idea Wasserpest, and thanks to everybody else in this thread! I should have built one of these years ago!