Remora's DO NOT overflow... If anything, after the cup gets full, the excess simmate will drain back into the tank.
The do not overflow into your carpet/floors or anything like that. That is one of the main reasons why remoras are so "good".
As for foam production, in a weeks time, depending on your bio-load, the cup will probably be full, especially if your tank has been running skimmer-less for a long time.
But the good news is, the skimmate will simply go back to where it came from, and that is your tank
