Due to spread of movies or online games which are applied with computer animation techniques, we can easily see scenes where numerous characters appear. In the case of large-scale crowd animation, if one were to increase reality of the scene, features of system would be lowered, and if one were to increase functioning of system, reality of the scene would be lowered. In realizing large-scale crowd animation with seafloor environment as background, the paper analyzed and applied elements that affect behavioral types of fishes; and by using concept of crowd, the paper enabled each group or object to control their behavioral type; by comparing and contrasting real-time calculation method as calculation method for animation and hybrid calculation method which is mixed calculation method, the paper seeks to find a method that increases functioning of the system while also expresses natural scenes.