Your pond sounds like what has happened on my local lake....The last 3 to 4 years..September comes and the creeks are blacked out with bait fish. You can throw a crankbait and bring in snagged shad every cast. The bass are there, feeding agressively, but are almost impossible to catch. Your bait, is just one in a million among the bait fish. Their is no reason the bass should key in on your bait vs the live bait. The bait explosion has been great for size, but has made it harder to catch them.