Silver carp and bighead carp were studied to see how they choose their food. In experiments, they picked smaller food particles based on size, but didn't actively choose their favorite plankton when it was evenly spread out. They could also pick where to feed. Silver carp ate more small plankton, while bighead carp ate more big plankton. For plankton around 70 μm in size, both species ate about the same amount.