Goldfish come in a number of colors and sizes. However, all goldfish have large eyes and keen senses of smell. They even hear exceptionally well. When hungry, goldfish also have a flexible palate, partaking of foods that are, among other things, slippery, slimy, fuzzy, crunchy, and sometimes squishy.
Goldfish in the Wild
Goldfish are natural omnivores; they eat all matter of vegetation, insects and their larvae, small crustaceans, zoo-plankton and even dead and decaying plant and animal matter.
Goldfish in Captivity
Goldfish owners can supplement their pets' diets by occasionally offering mosquito larva, blood-worms, daphnia, Brine or Mysis shrimp. Some keepers like to feed their goldfish chopped squid, mussel, and marine white fish -- special treats, as any marine pathogens in these particular animals rarely transfer to freshwater environments.
Vegetables are great for goldfish. Goldfish owners can boil or microwave leafy vegetables like lettuce and spinach, and even peas and garlic for a few seconds, softening the cellulose in the cell walls of the plants. After the veggies cool, they can be fed to the goldfish. Some breeders even offer their goldfish oats, believing they nourish the bodies of goldfish varieties with especially lengthy fins and tails.
Goldfish regularly graze along the bottoms of their underwater environments, which means that what they eat (besides store-bought fish flakes) is anything that lands or forms on the bottoms of their habitats. The algae that grows in their tanks, the fecal matter that stacks up after meals, the lost scales and detritus left behind by fellow goldfish, even the occasional pebble (though not a healthy treat) are all on the animal's menu.
Digital Vision./Digital Vision/Getty Images
Ruth Nix began her career teaching a variety of writing classes at the University of Florida. She also worked as a columnist and editorial fellow for "Esquire" magazine. In 2012, Nix was featured in the annual "Best New Poets" anthology and received the Calvin A. VanderWerf Award for excellence in teaching from the University of Florida.