It appears to me, that it isn't the ticked box that determines which tank is brought up, but the highlighted name. I think the ticked boxes only refer to those tanks in the cycling routine.
I agree that some clear indication of 'what does what' is needed!
Or to put it another way, - the documentation leaves something to be desired.
.... we are planning to build a pretty smart Help file online very soon. Which in my opinion is where ALL manuals and help files should be for all products (software, hardware, and services).
In my opinion, we should not have to go online to get operating instructions!