I just can't imagine five gallons of skimmate! Stinky!!!!
The 5 gallon never gets full, it may get to 3 but then it hits the float valve. The carbon in the top stops it from smelling, not really noticeable at all. I have also had that save my butt a few times, when my skimmer went nuts and drained 3 gallons quickly, turned off and informed me of the issue.