How to have a smooth/sharp fluid mesh


I’m trying to create a transition from a solid object to fluid with the rigid body and fluid simulation. When I bake the fluid it always appears bumpy and not flat like I want it to be. I’ve tried everything I can with the Positive and Negative Smoothening, Concavity Upper and Lower, and nothing seems to make it completely flat.

I don’t even know if this is possible because I have tried many different things. Any help is appreciated! Thanks!