Simple waterer spike for pot ease for refill you can use regular PET Bottle 18mm diameter (Coca Cola ect) from 0.5l to 2l
different for this version is you can slowed the waterflow not get empty if is in pot enoght water
I have parametric version for this spike in openscad (can set some size or options or flow)
if somebody interest let me know
scad 18mm cap remixed from https://www.thingiverse.com/thing:1654620
The author hasn't provided the model origin yet.