Particle interaction in viscous fluid

Hello fellow artists.
I am trying to implement elongated particles flowing within and being carried by a viscous fluid. The kick is that this has to be real-time with possible user interaction.

So far I have managed to get unrealistic results, like both fluid and particles flowing, but particles not really being carried, or complete lack of interaction between the two.
Any help would be appreciated.
Thanks.

Edit for more info:
What I’m trying to get is metal fibers flowing in concrete. I’m at my wit’s end, so pretty much any suggestion would help.