I agree that composting fish can be a little tricky until you get some experience. Your nose tells you how you are doing. Vous ecrivez tant. I'll have to lighten up on the questions, otherwise you won't have time for a life. Oyster sales are good in November and December.
Oysters are very big in France.
We grow clams and mussels and move a little crab. No fish, but I get unlimited fish scraps for composting. Also I have a source for shrimp shells. All this stuff from the sea makes a good garden. Fish and all these sea materials are very high in nitrogen.