In "Scuba Scuba Doo," Eustace never called Courage a stupid dog, rather, he called him an Idiot dog, and a lousy stinkin' dog.
When Courage turned on the giant vacuum, the remote got sucked in, but after the garbage got sucked in, Courage turned off the vacuum with the remote. Didn't it get sucked in?
According to the segment "Windmill Vandals," if the windmill stops, vandals attack. Vandals didn't attack in "Conway the Contaminationist" when the windmill stopped turning.
Conway: Silly dog, you'll need much more than a bathroom to clean this up.
Muriel: OOOOHHHHH, it's kind of burns!
Conway: That only means it's working!
Conway: Out with the good air, in with the bad! Out with the good air, in with the bad!
Muriel: You finished the whole thing, Mr. ...
Conway: The name's Conway, and yes, thanks to you, I am on the way to full recovery!
Conway: Live long like Conway!
Ma: Stupid dog!
The coral people resemble the 'incredible' sea monkeys from the old adverts (though admittedly, they weren't that incredible).
Episode Title: Scuba Scuba Doo
The episode title is an parody on Scooby-Doo's quote: "Scooby Dooby Doo."