The distinctive taste of a Marseilles Bouillabaisse depends on the presence of a variety of Mediterranean fish (especially the strange local rockfish, rascasse). It is their particular aroma on which the dish’s fame rests & without which it is just another fish soup.
The fish must include at least four of the following (preferably more), extremely fresh: rascasse, rascasse blanche; vive araignée (weever fish); galinette/grondin (red gurnard); St Pierre (John Dory); baudroie/lotte (anglerfish/monkfish); fiéla/congre (conger eel); scorpène/rascasse rouge (scorpion fish).