It's spring and a young male fish's fancy turns to thoughts of female fish. When you see your fish chasing after each other, sometimes even removing scales or acting as if they are fighting, they are really spawning and you will soon be a goldfish grandparent.
Fish are not good parents. The moment the fish is born, the parents try to eat it and are often successful. Goldfish are born a grayish, brownish color to give them a chance at life and obviously, some make it.
If you give those babies a place to hide, they have a better chance of survival. The best place for fry to hide is in the fine roots of water hyacinth. Scatter the hyacinths around your pond so the fry can stay there until the coast is clear. When they get a bit bigger, they can survive much more easily.