Take a pic of urs.. Never seen a Areo cloner with a dome.
my old botanicare 156 or 165 came with one but never used it, my newer botanicare 180 didn't neither did my new turbo clone 32 aka the experimental torture chamber.
that's one of the coolest reasons to use aero- I hate dealing with the lid.
never had any droop without lid in aero btw.