Catch up TV on Monster Fish. Watch the latest and all other episodes of Monster Fish now online, broadcasted on 7Two. Catch up on your favorite 7Two TV show: Monster Fish. Replay tv on its best! In his quest to save the world's big fish, aquatic ecologist Zeb Hogan has wrangled what's currently the world's biggest known freshwater species, the Mekong Giant Catfish. But is it really the biggest? We'll join Zeb as he travels the globe, seeking out the leading contenders in a quest to better understand them as he fights to protect them.