I feed carnivore sticks and veggie sticks from yourfishstuff.com. great prices on my opinion and my oscars love that stuff. goldfish and guppies love it too.
Repashy gels. Fruits and veggies from mine and my neighbor's garden, worms from my own colony. Left overs from dinner. Mosquito fish for Lazarus every now and then because I have a billion of them.