Summary

This is to adapt a cheaper Bunnings Bucket to Dani's Indoor Grow Towers.
The original buckets cost $14 in my area where Bunnings generic branded bucket was $3.35 and 10ltr instead of 5ltr.

Hats off to Dani for creating an awesome Tower Garden System!
https://www.thingiverse.com/thing:6444781

If you design your own.. 210.2mm is the size you want to make your opening.