Instructions
Watch the eggs for movement. As the fish fry develop within the egg, they start to move making the egg wiggle. You may see the wiggling just a day or two after laying.
Look for shapes inside the egg. You may be able to see the eyes, which will be darker than other parts of the fry. Unfertilized eggs will be clear or solid white in color. Like the wiggling, within a day or two after laying you should see some development within the egg.
Watch for hatching within three to four days after the eggs have been laid. Leaf fish eggs develop quickly. If they do not hatch within five days of being laid, they are probably not fertile or did not survive.
How to Tell If Leaf Fish Eggs Are Fertilized
Appropriately named for its leaf-like appearance, the carnivorous South American leaf fish (Monocirrhus polyacanthus) only eats live foods and rarely breeds in captivity. Because of the difficulty in breeding these fish, they are rare in the aquarium hobby. This can make seeing their eggs laid on leaves, rocks and other flat surfaces with the male standing guard very exciting for any fish hobbyist. It will only take a few days to confirm if fertilization occurred.