aquarium burrow hide 3d model

Create a 3D printable aquarium burrow hide. The object must have only one entrance: a round or oval opening on the top surface. From this top opening, a smooth vertical tunnel goes downward into a large hollow cave chamber at the bottom. The bottom chamber should be spacious, rounded, and safe for aquatic animals to hide inside. The outside shape should look like natural compacted clay or eroded earth, organic and asymmetrical, with gentle uneven texture. The model must have a flat stable bottom, thick durable walls, rounded edges, and smooth interior surfaces. One solid FDM printable object. No front entrance, no side entrance, no skull, no face, no shell, no monster, no plants, no animals, no background.