Hello CupOfTea, google “strata schemes management act 2015” and scroll down to section 109 “Cosmetic work by owners”. There is a list of examples of “cosmetic work” which does not require approval of the owners corporation.
Paragraph 5 lists work that is not included as “cosmetic work”. Here is your problem:
“(c) work that changes the external appearance of a lot, including the installation of an external access ramp,”
A hook on a balcony ceiling does change the external appearance of a lot.
You would have to seek permission from the owners corporation. This would require a vote of all the owners at a general meeting. If they decline, they could order you to remove the hooks. If you refuse to remove the hooks, I wonder if the owners corporation would go as far as applying to NCAT to have your pot plant hooks removed. It seems so trivial.
You could explain to the NCAT member that they’ve been there for years and nobody keeps records for that long. You could also apply to NCAT yourself to have the hooks approved. I think the NCAT member would think why is everyone wasting their time on this.