There is problem to get nice self-watering planters here. This thing is just inner part of planter.

Source OpenSCAD files are attached, so inner diameter can be adjusted.

To have working pot buy nice pot (ceramic :-) and small piece of tube.

Consist of 2 files:
-kvetinace: bottom of the pot
-trychtyr: funnel

RepRap

Rebelix

No

Doesn't Matter

Supports are not needed. Only use small brim for the funnel.