What is the status of your LMB population , balanced , crowded , to few LMB ?

You could always not stock them all but instead find a neighbor or friend's pond that could use them. With permission , of course.

If you have FA it is not just because of your neighbors fertilizer. If he fertilized and 3 weeks later FA shows up at the surface of your pond some distance from his field, then FA was there on the bottom well before he fertilized. Ask him if he does the same thing every year. If he says yes then you will probably have the same FA as in prior years.