The submarine tour allows you to go underwater in a submarine and observe the various fish in the area. It is in almost every location, and some areas even have two or more. The submarine tours allow you to memorize the shapes of the fish so that you can recognize them in the water, and it allows the player to preview fish that haven't been caught yet. Additionally, some uncatchable fish can be rarely seen on some submarine tours. If the player sees a fish that can't be caught, it will be unlocked for the player's aquarium.