The Sandbox mode can be accessed after earning either the Silver Trophy or the Gold Trophy from Challenge Mode. Entering the "Konami Code" at the main menu screen will bring the player to Sandbox Mode.
|↑ ↑ ↓ ↓ ← → ← → B A|
While in the Sandbox Mode, players have the ability to spawn any type of fish, pet or alien (excluding Cyrax). Each entity has its own corresponding key in the keyboard.
|"+" and "-"||Rotate Tanks|
The music and backdrop at the beginning will be from the last tank played in Challenge, Time Trial, or Bonus Adventure. If none have been played, Tank 1's music and backdrop will be used. If the backdrop is changed, the music will not change; it will use the last music from the last level played.
- The only fish that cannot be spawned is the king guppy, although this is likely because king guppies are simply an upgrade from large guppies.
- Star guppies, however, can be spawned due to a lack of available star potions.