Oscars are omniverous. Carniverous would mean they only eat meat in their natural setting. In the wild oscars will eat other fish, insects and larvae as well as fruit and plant/veg matter. They should be given the most varied diet you can provide with a good pellet as a staple.
I feed my oscar blood worms, shrimp, insects, and pellets. Some people say oscars should be feed plant matter or veggies too. Every source on the web indicates oscars are carnivors. What do you think?
I feed my oscar pellets that contain veggies as well as the varied diet you talked about. It has grown into a beast over the last couple years with no signs of HITH. I don't think vegetables are a necessity, but I would recommend a veggie based pellet like Cichlid Excel as a complement to their diet.