This is my new test with Houdini. I learned how to capture my model with a simple bones system, and animate them with Chops using sin ops with lag ops. Then I generate and animated texture in the fish with Vops for the particle emissions. The same geometry acts like collider. And finally the particles have an expression to reduce their scale with the age of each one of them. The camera is travelling on a curve and exported to Nuke for the final composition. Rendered with Mantra with z pass.