I just did some research right now and think I have a clearer
understanding of the difference between the fumet and stock.
From what I can put together, the fumet de poisson (fish fumet)
is just a more concentrated stock. As far as ingredients and
cooking are concerned they are the same save for a few herbs thrown
in at the end of a fumet. Those ingredients vary from recipe to
recipe however so I apologize for the vagueness.
I am in culinary school and this was an assignment from our chef
instructor so when I turn in the assignment I will hopefully be
able to clear up any questions that might have been, or should I
say, are left unanswered.