Shoot fish with a harpoon. The underwater environment makes for a relaxing shooting game.

Use the mouse to control the harpoon.
DO NOT shoot the ornamental fish, they are protected and you will lose your license.
Also avoid the porcupine fish because they will make you lose money.

HINTS: Pay attention to how much you earn for each type of fish. The eels pay the best at $500 while the bright red fish are worth only $25.
Between levels shop carefully, don't pay for things you don't need because your ability to move to the next level is determined by your cash balance.