Over the past month I have made many changes to my .40 acre pond.Air from Clean ponds,an On Time feeder,many more fish,and Aqua Max 500.I'm not sure what has had the biggest impact but when that feeder goes off I would not put my hands in the water.They eat that Aqua Max up.The pump has probably not made a difference yet so it must be the feed.Watch out big Flatheads.I have a well stocked and well fed bait pond.Thanks to everyone for the advice.