Some time ago Naiad, was one of the most popular softwares to create Fluid Simulations.

Actually naiad continue as one of the best fluid softwares after the Autodesk adquision, is a complex software to start to play with it, but here you can download my own Waterfall scene if you wan to learn something of this great software.

https://dl.dropboxusercontent.com/u/30398202/Wordpress/Naiad_Waterfall.rar