Phil, My pond is about the same size as your and probably in about the same condition. I had alot of skinny bass 4 years ago so started removing pretty heavy. In 2008 I added 2000 5" bluegill and 10,000 Threadfin shad and removed 250 lbs of bass that year and still no signs of improvement. The next year I added 150 lbs of crawfish and took out another 200 lbs and then last year I lost my shad so I removed 250 Lbs again. It got to a point where my fish were so hook shy that they were impossible to catch. but like Greg said you need to shoot for 300 lbs. Better catch as many as you can before you add the crawfish. Mine got really tough to catch for a few months after adding them. Kinda hard to catch them when they arent hungry.