Escalating this to Fair Trading would tescalate this even further than you clearly want to go.
How about asking your secretary or strata manager, on the basis of no names, either of the copulators or yourself, to send out a reminder to all residents that offensive activity on common property is a breach of your by-laws and apartment balconies are common property.
If everyone gets the notice, then fingers need not be pointed. For your reference, the model by-law (which you probably have on your schemes’ books), is by-law 7.
7 Behaviour of owners, occupiers and invitees
(1) An owner or occupier of a lot, or any invitee of an owner or occupier of a lot, when on common property must be adequately clothed and must not use language or behave in a manner likely to cause offence or embarrassment to the owner or occupier of another lot or to any person lawfully using common property.
(2) An owner or occupier of a lot must take all reasonable steps to ensure that invitees of the owner or occupier—
(a) do not behave in a manner likely to interfere with the peaceful enjoyment of the owner or occupier of another lot or any person lawfully using common property, and
(b) without limiting paragraph (a), that invitees comply with clause (1).
Again, as I said, your balconies are common property in most buildings. Make it clear that you are not looking for any direct complaint or action to be taken – just to let the bonkers know they can be heard and that’s not how to behave in an apartment block.
Do it this way and the worst that can happen is that there will be a whispering campaign trying to establish who is doing what to whom, where and when. Oh, the scandal!
The opinions offered in these Forum posts and replies are not intended to be taken as legal advice. Readers with serious issues should consult experienced strata lawyers.