Yep Selena, it's never a good idea to release pets in to the wild. Even if they are native to the area, they may have diseases, or may be resilient to disease that naturally controls the population in the wild. Also, maybe not so much with fish, but pets in general may not have learned the skills to survive in the wild.
Oh, and for us in the U.S., that would be just under 6 feet in length and 250 pounds for that record holding fish.