Tested with my FLUVAL AquaClear 50, but should work on most other AquaClear hang-on-back filters as I believe they all have the same intake tube diameter.

Printing

I printed it with a 0.1mm layer height (but used adaptive layers to cut down on print time) and 3 raft layers for better bed adhesion.

Use in aquarium

I plan to keep this in my aquarium long-term, but you should do your own research about 3D printed parts in aquariums and evaluate your comfort level with it before doing the same. Based on what I read from various sources, PLA should be safe, especially if it is “natural” (no color additives), so I used 3D Solutech Natural PLA, and hopefully that will be fine. I also read that it may biodegrade over time (years), but I can reprint and replace it if that happens.

Modifying

I designed this in OnShape, so the original CAD model can be found here, and an exported STEP file is available below in addition to the printable STL and pre-sliced gcode.