Looks like that's exactly what is done in the photo with the sun corals under there.If you were dedicated about it, you could use nps on the undersides.
Probably not, those display tanks at events like this often have "loaner corals" or corals from one's own personal stash and are used for display purposes only. Sometimes sold the last day/after the show at a fairly good discount too.Those acan colonies must have cost a fortune
Interzoo is 4 days I believe, so probably 5 days with the setup day.How long is that tank allowed to “live”