Debug mode:
Hold X + Y on controller one, A + B on controller two, and turn on the SNES. The phrase "Debug Mode" will appear on top of the screen to confirm correct code entry. Begin game play and use the following controller actions for the corresponding effects:

Adjust conditions
Hold A on controller two on the boating screen and go to the casting screen.

Speed up time
Press X on controller two at the boating screen.

Catch random bass
Press B on controller two at the casting screen.

Catch random fish (non-bass)
Press Y on controller two at the casting screen.

Catch a lunker
To catch a lunker varying from at first 21.8 lbs gradually declining by .2 lbs., press Up on controller two.