I have a ball with a rigidbody and it has fluid with a type obstacle. But when it falls in the water I don't get a splash or anything. What I want to happen would be the ball to fall in the water, splash and also maybe the ball float a bit. How would I do this?
To have the rigid body affect the fluid, simply go to the fluid obstacle settings and check Export animated mesh. However, while the rigid body will affect the fluid, the converse is not true, so the fluid will not slow down the rigid body in any way.
Keyframed animation is the way to go in this case.