In the first two seasons, the diner where the characters always eat is "Chokey Chicken", which has a giant choking chicken as a mascot. In the third season, "Chokey Chicken" became "Chewy Chicken". There are many hidden sexual references in Rocko's Modern Life, and this was one of the more blatant ones. It was changed because the show is designed for a young audience.
Richard Simmons once offered his voice and semi-likeness to an aerobics trainer in an episode during the first season.
Tragically, prior to the production of the first season of the show, Joe Murray's first wife committed suicide. Murray believed he would create one season for the studio, move back home, and tie up loose ends but to his surprise Nickelodeon approved the show for new seasons, but only if Murray was "up for it". Murray's experiences with the studio and his shock at the success of the show were parodied in "Wacky Delly (1996)."
Rocko was originally supposed to be colored yellow. The color was changed because a toy marketing company informed Nickelodeon that they were interested in producing a doll, but already had a character that was yellow. The color was changed to beige, and, after the pilot aired, Nickelodeon got rid of the toy deal.