Hi, I want to be able to see and control: pH, Temp, CondS, ORP in an aquarium locating in another room from the main aquarium in which the PIII ex is connected.
So, I will need an expansion Box.
Is there only one Expansion Box in which I order seperate extension cards to build it or it comes with some slots in it?

What is/are the PL numbers to make the order?

Thanks!