Color Change in Fish

Question
I am doing a science experiment on whether or not fish will change colors when their food type is changed. Could you recommend a type of fish (prferably inexpensive) and type of food for this experiment?
Thanks!

Answer
The least expensive fish you could get is a feeder fish. So something like a guppy or comet goldfish.
You can help bring out color in fish by feeding them different herbs. For example, a fish that is red will turn a more vivid red if they are fed small amounts of paprika with their food.
Just try to make sure you aren't getting a fish just to experiment on it and then let it die. If this is the case, please find something else for your project, as it's not really fair to the animal.
Hope this helped.