The wider the variety of foods you feed the better! The Angel will probably appreciate seaweeds. I feed my fish Formula One, Prime Reef, Special Formula VHP, Emerald Entree, Marine Cuisine, Mysis. These are all frozen foods, although I think Formula One and Prime Reef also come in flake form.
I always soak things like Mysis, Emerald Entree and Marine Cuisine in garlic extract or vitamins like Zoe, etc. Also, for some reason my fish only devour all of Prime Reef if soaked in garlic extract; otherwise half of it goes floating away uneaten.
At least one company also recently started producing arcti-pods. (Do a search on google.) You store these in a bottle in a fridge. They're bright red and larger than cyclop-eeze. And all of my fish go crazy for them. In the water column they look like live brine shrimp, but are very nutritious.