Instead of normal fish curry, I tried this Spicy Nadan Tomato Fish recipe by Roselle which is a hit with my family. It has sweet, slightly hot and tangy taste the way I like it. Sweetness comes from the onion used and recommended that you lightly fry the fish before adding to the gravy.
If possible try to use bigger fish with less bone and thick flesh. Adding chili powder and tamarind can be adjusted to your liking. This recipe produces rather thick curry but if you want more gravy, do add more water but not too much.