Taking fish out of the U.S.

[Nebraska_cichlids]

I've brought fish over from Europe to the U.S. on numerous occasions. My next transactions is shaping up as if it was going to be a trade, i.e., I would need to bring fish from here to Germany in order to get (some of) the fish I want to bring back. Has anyone any experience with export (U.S.)/import (Germany) requirements? Thanks.