I'd love to help, but "curry" is just so broad of a term. For example, I make three different masala blends (curry powders) for different uses. Even a quick search for curry popular in Durban gives tons of recipes. Just about any of them would work with cod, if you substitute for things like apples. How spicy do you like it? Sharp like red masala, savory like yellow or a rich, herb-like green? But take a look at the Durban curry recipes on this page: Curry Recipes
. They may be helpful. I don't recognize half the food terms that they use, like "fish masala" ... that means a blend of spices for fish, but what's in it? LOL Good luck!