Crappie fecundity up to 188,000 vs BG 80,000 per year.
Spawning temps as low as 56 degrees vs 72 and 75 degrees for RE and BG. In addition I have been told ( but have seen no published info) that crappie year class varies wildly based on existing population dynamics from good numbers of large fish to massive numbers of small fish in a cycle. It is the cyclical spawning, along with those noted above, that makes it next to impossible to manage crappie in small ponds. I have seen info that indicates that gizzard shad have the same ability to control offspring numbers based on population dynamics. These are the know risks I was talking about in my first post.

Big Pond based on the 5 acre pond and fish you listed I think the risk level for either crappie or GG is extreme. I would think that after a few years you would be facing a complete renovation. I can only think of a couple of examples for the use of Crappie or GG in a mixed pond and they involve using them as forage for large existing predators like blue or flathead cats or large LMB or HSB with the idea being that they will all be consumed and even these involve some risk. ewest