What sounds do goldfish make?

Normally goldfish make no sound, but when competing for food or playing they may collide with other fish or the tank and produce faint chirping or gurgling sounds. In addition, when oxygen-deprived they surface and make bubbling or popping sounds, but these are very faint and hard for us to hear. Because fish have no vocal cords, they can only make sound through other body parts, such as bladder-muscle vibration or blowing bubbles..