Iranian director Masoud Jafari Jozani was a member of the festival's panel of jury, IRNA wrote.
The festival hosted 12 countries fielding 23 movies for awards while 55 others were slated for screening.
'Mermaid' had earlier won the Best Screenplay and the Best Film at the Mediterranean Festival Cannes.
Aqababaeian's film is about Younes, a survivor of a diving team in Iran-Iraq war, who lives along the shores of the Persian Gulf. He wants to set a statue under the Persian Gulf as a memorial to his friends who were martyred in the Persian Gulf. However, he encounters water pollution created by oil companies.