Alright, so there's nothing to do really after the visit to the place where the BIFF is going to be held. They were just setting up the place and it's not like the event is held that day. Opposite of BIFF, there's something called Jagalchi Fish Market
Jagalchi Station (Busan subway line 1), Exit 10.
Turn right onto Jagalchi 3(sam)-gil Street.
Walk for 5min, then turn left to arrive at Jagalchi Market.