I figure the fish have a natural food source and won't be harmed by some worthless starch they seem to treat like junk food. Turtles the same way. I never considered the pond an aquarium that needed a supply of fish food - a supply of which will never happen. Zero dead fish so far this year as far as I can see floating, but then again, except for heron kills, no dead fish for 10 years.
Of course, it's your pond to do as you please with, but if you're going through the effort to spend the time to throw bread, you might as well derive other 'low-hanging-fruit' benefits from actual fish feed; those benefits are many.
Also, I didn't say that bread would kill any fish, just that it has no nutritional value for them.
