URUP There is a possible solution that was in a pond boss magazine article for people that want some crappie to catch in a small environment. The thought was to same sex adult crappie so that there will be no breeding and add them to the pond.

On a side note I have a 3 acre pond that I put in BCP last year. I am predator heavy and intend on using the pond for high volume fishing. It will be years before I can report how it works out in the long run. Crappie in a short term tend to do well in smaller ponds. It is the long term high populations that stunts the fish. I also put them in a pond that I can drain and refill in a short time span so if things go wrong for me it is not a big issue.

Also here is video you might like.
1.5 acre Farm Pond Crappie fishing