The only thing i really know is ,I have been overrun for several years and have given away thousands of CC every year and it seems to get worst. I had Missouri Department of Conversation MDNR hear over 2 years ago and they asked Columbia University to take some tests and stated there is a wide fluctuation of water temperature by all of the geothermal tubing and using water from the 750 ' well to keep the pond full.
I have two separate geothermal systems to heat and cool separate buildings. The university said I had as much as 20 degrees difference in temperature. from one end of the pond to the other at the same depth. I know it doesn't freeze over in the winter.
I have added two aerators and that has not helped. I was told I should have had 2 acres for the size of the geothermal.
I have no idea about spawning except what I have been told. i was told that the water conditions apparently cause the CC to spawn several times each year but not the same CC each time. They indicated the pond is an anomaly .
I do now i would drain it and start over if it was not for the geothermal.
That is why i have a 20 CU.YD. holding net so i can filter out the over stocked fish.