This is a nice and very easy to print, under-the-gravel/sand viewing cave for use in a medium size fishtank. It's meant to be up against the glass, displacing any gravel, sand, or what have you. There are two versions available, with and without the signs. Sharp edges are filleted. You'll notice the small “ladders” with just enough grip inside for use by anything with claws that manages to get in there. We don't want anyone getting stuck! There are mild chamfered edges to help hold the height as it occasionally can get knocked about.

No supports are needed for printing. Print as oriented in the mesh. A large layer height should be just fine.

For marine safety, this should be printed in ABS, PETG or PLA (preferably food safe). Remember to cover the center part back up with gravel so as to truly hide it!

Dimensions are in mm in the image.

Update 2/24/2024: After some requests, I have added a second version with a front piece to decrease the media falling into the cave.