HomeCover CoverUSA USA and WorldHit itat The world's oldest living aquarium fish lives in San Francisco By Pen 360 Press 2023.09.21 0 1561 FacebookTwitterPinterestWhatsApp Methusal, an Australian lungfish (Neoceratodus forsteri) at Cal Academy's Steinhart Aquarium, is 92 years old, making it the world's oldest living fish in an aquarium. (California Academy of Sciences via Bay City News) By Bay City News.