First and Foremost Merry Christmas!
Just a quick update regarding this project.
I have been accumulating all the parts I require to build a portable demo rig of this project and it has took some time. Today I have finally ordered the last pieces to be able to finish off this rig on my return to work in the New Year.
The rig is going to be built upon a two DIN rail system mounted to two triangular mounts; the front rail will hold the Pi, Arduino and relay modules, and the back rail will hold the mains power distribution, 12v power supply, 5v power supply and 4 rail mountable 13A sockets.
This will keep the project small and compact, will keep the wiring neat and hidden between the rails, and will look great on my desk :-)
If space allows I am also going to mount the original Aquariumatic slave module that only worked via USB, and I will rewrite the old code for the unit to be supported on the current Pi. It'll allow me to show the progression of the project.
Pics will come in the new year; all parts apart from the 13A socket are currently in my possession so we are good to get going!