It appears at the beginning of the episode when SpongeBob needed some money from his bank account to buy Mermaid Man and Barnacle Boy trading cards. Quincy, the bank teller, gives SpongeBob his money, but SpongeBob is very picky on what money to give Mermaid Man and Barnacle Boy. Quincy and the customers are annoyed by this after a while, and, soon, Quincy kicks him out of the bank.
It may have appeared as the bank inside interior is shown in this episode.
The Bank appears when the Light Blue Cellmate was explaining to Plankton how helpful chum is in robbing banks. The Light Blue Cellmate threw a bucket of chum inside the bank causing the place to get gassed up and the Light Blue Cellmate was able to escape with the stolen money. However, he was caught soon afterward.
"Goodbye, Krabby Patty?"
Mr. Krabs goes to the bank and gives the bank loaner a check. The loaner gives Mr. Krabs a huge sack of money, which resulted in Mr. Krabs fainting. The loaner pushes the bag off of the counter.