Designed a semi-automatic fish tank water changer yesterday using two USB bird bath pumps I had laying around. Mounts on the side of our small tank with one pump sending dirty water to one side of a bucket and a second one that refills afterward with temp-adjusted conditioned water from the other side. Tube routing was a fun touch.

It’s quite satisfying when a v1 design tossed together in <1 hour on an iPad + Shapr3D just works (some of the credit goes to the Bambu A1’s dimensional accuracy).