Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Character mistake: In "Help Wanted", Stephen Hillenburg's name in the "Written By" section of the title card is incorrectly spelled as "Stephen Hilleburg."
Jellyfishing / Plankton! - S1-E3
Character mistake: In "Plankton" when Spongebob is in Plankton's lab, he says the ingredients in a Krabby Patty. He doesn't mention the secret sauce.
Answer: I believe this is the Season 6 episode "Spongicus".