The Chocolate Pom Pom Goldfish (Carassius auratus) is a rare, fancy ornamental goldfish prized for its deep chocolate-brown body color and distinctive feathery nasal “pom poms,” offering a unique, long-term aquarium companion. They grow to 6-12 inches. You would need a minimum of a 20- 30 gallon tank. They can live up to 20 years in ideal conditions.