Place the head and bones in a large enough pan
Cover the head and bones as much as possible with the water
Add salt
Bring slowly to a simmer; when observing scum and froth, remove it with a sieve or straining tool
Then add the other spices and herbs
Continue to simmer doe 1.5 h
Then take the pan off the fire and take out the bones and head from the pan and place on a cutting board or the like
Remove the good fish meat and reserve. Discard the rest
Strain the broth through a wide maze strainer
Place the fish meat back to the broth. Taste it and bring to taste with salt, a spoon of sugar (optional) and pepper,
Fish broth spoils quickly, especially in hot kitchens, and so refrigerate as soon as possible or freeze it in a a few Ziplock bags