mussels as adults are too big for redear, though they might control juveniles. There are very few mussels that fair well in ponds. The eastern floater is pretty common in ponds. Largely due to the fact that it's host species include bluegill, and pumpkinseed. The range map in this PDF is incomplete, as I have found them in Ohio, and have to assume they are probably in adjacent states. They can easily come into a pond hitchhiking on the gills of stocked fish. I hope to have some in my pond at some point.
http://www.naturalheritage.state.pa.us/factsheets/Pyganodon%20cataracta.pdf
