Hen not laying fertile eggs
I have pair red head Gouldian finches from past one year. Female is not laying fertile eggs. She has layed eggs three time in past one year.
Just as it is with humans, there are many possible reasons for infertility. The male could be sterile, the vitamins and minerals needed for successful embryo development may be insufficient. There are nutrients that are necessary and must be available to Gouldians when breeding. The pair may be incompatible and not care for each other. The temperature, humidity level as well as the number of sunlight hours and availability of full spectrum light can all be contributing factors. If the environment and diet are set up correctly and providing all that is needed, the first thing I would do would do would be to try the female with a different male.
I hope this helps, Jeanie