Could very well be the ammonia as it's very toxic to fish.
Is this a new pond with only fatheads? If not, and the ammonia is the culprit, you should see other species dead too.
You need a berm or something to keep wash from the farm field out of your pond. You could get herbicides are pesticides after a heavy rain too which can also be quite toxic to your fish.
Last edited by Cecil Baird1; 06/04/10 11:08 AM.
