Add the Iru (locust beans), dried shrimps/prawns, and stockfish or any protein of your choice. Cover and continue to cook to allow the fish to absorb the liquid if the soup is getting thicker for you add the remaining water/broth.
If you're using stockfish make sure you soak it in hot water and salt overnight and if possible cook the soup a day before you actually want to eat it, that way it would be softer if not you won't enjoy the stockfish.
Also, if you're using stockfish you need some liquid in the soup because the fish would absorb the liquid very quickly.