I have never seen FA growing on YP eggs. As mentioned possibly your eggs are dead. Try doing what I suggested above. "To tell if they are fertilized pull a small piece off the ribbon or look at the ribbon closely. If the centers are amber or clear-yellow colored they are fertile if the centers are white they were not fertilized. You may see amber and white egg centers in the same strand indicating partial fertilization of the strand and due to too few males. As the eggs develop after 5-7 days the centers will appear dark due development of the eyes on the embryo." Dead eggs will have white centers and developing eggs close to hatching will have black centers.


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