Tough question, I’d just have to answer it to the best of my ability. I wouldn’t know in terms of nutrition, but fighting fish absolutely loves live foods such as bloodworms, mosquito wrigglers and full grown brine shrimp. Usually you can get hold of these from your local fish shop, but it’s also quite easy to go out and find it yourself.
There are kits that come with brine shrimp eggs and growth food.
For mosquito wrigglers and bloodworm just put a small piece of fruit or vegetable in an old sock and leave it in a bucket of water in the garden for a week. I guarantee you’ll have heaps of little wrigglers after a while. Let them grow (just not for too long!!!) and then simply pour the water through a net catching the wrigglers.
Other than live foods pellets work just fine – that’s what we feed all our fish most of the time.