Press [Shift] + 4 to get more money. (Using this cheat will cause your marine
 tank water to become dirty!)

 To unlock the hidden mermaid, place the mermaid statue in one of your marine tanks.

 Just rename one of your exhibits Xanadu and you will unlock a unicorn in the
 animal panel. You must rename the exhibit. If you try to name a new exhibit
 Xanadu, your game will probably crash.

 After winning the Shark World scenario, you'll unlock the photo booth. Check
 your structures menu and it'll be there.