What are fishes favorite freeze-dried food?
Something soft and wiggly is better than freeze-dried. Skip freeze-dried and go for live or frozen bloodworms, brine shrimp or daphnia. These will be picked at by all, maybe even the pleco. What species of pleco do you have? Some are more carnivorous than others. FYI both the tetras and cory do better in larger groups, at least 3 or more for the cory and at least 6 or more for the tetra, you would be pushing it in that size tank though.