Crupski is a small fish (almost half the size of Mr. Krabs) who is light green in color with lime green arms. He wears a white dress shirt with a blue tie, and dark blue pants with a brown belt and black shoes.
In the episode, Crupski was paid by Mr. Krabs to build the Krusty Krab Stadium. He also hired Charlton Hawkfish to install the plumbing. However, it turns out that Crupski added a reducer to the mainline and the pipe is even made of cardboard much to the fury of Charlton. Crupski replies by saying it's a way to save money much to Mr. Krabs' delight. Later, Crupski, Charlton, and Mr. Krabs are watching the game but Charlton is more worried that the pipes are going to burst. Crupski ignores his warnings and continues eating chips.