Paul Scheer, seen in the the first Piranha 3D, recently discussed the upcoming sequel with radio DJ Tom Sharpling. Paul mentions many details about the film in the interview below including that apparently the piranha's are attracted to the smell of chlorine, thus the water park theme in this film. Also that Charlie Sheen isn't in the film while Gary Busey will be playing the role of a farmer. So check it out for yourselves and look for Piranha 3DD in theaters November 23.
Source: YouTube