Just a humpback whale coming out of your wall (destined to mate to a possom, but I figured while it lived it might as well look like it'd fit in the aquarium).

Printing notes.  Wireframe v1 has some minor dangly bits if printed organic tree supports at 5 degrees in Prusament PLA in Bambu X1C so I may update for robustness.  It looks fine though up on a wall with the danglers hidden “behind” it. :)