This is OpenJSCAD source for creating a 3D model of an aquarium water filter output baffle. This code can pasted in at http://openjscad.org, then rendered viewed. You can also generate a .stl file for 3D printing this model.
This is a baffle for the water that flows out of the filter that comes with Minibow Aquariums. This one was designed for the Minibow 5-gallon aquarium filter, but I believe it will also work for other sizes that use the same water filter (model: MB1).
Without this baffle, the water output flow from the filter caused enough turbulence in the aquarium to affect our Betta (especially when it came near the surface). This tray prevents the direct outflow and allows it to disperse through the holes in the bottom of the tray.
Another benefit of having this baffle in place is when you are changing or adding water. You can pour it into the baffle tray which will help minimize disturbances in the tank.
Generated models based on this code can also be found on the Thingiverse site at http://www.thingiverse.com/thing:1796487. The images directory contain some pictures of a 3D printed version of the model and how it looks in use.