This from an article on Eurogamer.com

.........
As well as version-specific controls, the DS release also promises over 750 fish - nearly twice as many as on the PC - along with 3D environments, new tank decorations, and four speed options
.......

If you want to read the article here is the link:
http://www.eurogamer.net/article.php?article_id=77664
_________________________
Carla
Executive Producer
Last Day of Work