Summary

A self watering pot in a space-efficient, awesome square shape.

120x120x150mm / (4.7x4.7x5.9'') external.
and
120x120x100mm (4.7x4.7x3.9'') external.

Scaling it down will work, since wall thicknesses are 2mm - Upper, 2.5mm - Lower.
Just be sure that it has at least two perimeters.

A few suggestions:

1. Don't use PLA if you gonna use it anywhere near direct sunlight;
2. Use either "random" or aligned seam alignment for a higher chance of water-tightness, as well as 101-104% flow.
3. Printing orientation just like on the pictures and in the stls. Z up.

Comment or message me if you need Fusion source file. It's messy atm. And I don't plan on optimizing it, unless someone needs it. Alternatively, hang around my profile page for a couple of days for a configurable F360 version.

Step file attached. Stl's are lame.

Feel free to comment. Any criticism is welcome. And if you need something like this made or rendered for you, find me on Upwork

The author of the design is https://www.thingiverse.com/emptiness_between_the_stars/designs 
Source : https://www.thingiverse.com/thing:6400198