What Do Fish Eat?

In the wild they feast on live fish, insects, larvae and crustaceans. All fish require some amount of protein; however a carnivore’s diet should be made up of 45% to 70% protein. In addition to proteins, these fish also need some fats to insulate the body, and small amounts of carbohydrates to provide energy.

What do fish eat in the ocean?

Fishes eat mostly eat zooplankton, other fish, algae, sponges, fish eggs and larvae, jellyfish, worms, crustaceans, and yes, floating insects, but not insects we get used to on the surface.

Fish eat a wide variety of things; however their specific diet depends on their natural environment, the eco-system in which they live and a host of other reasons.

Some fish are sluggish scavengers and will eat whatever they come across, whereas other fish’s diets consist solely of eating other fish.

Whilst many humans make their diet a lifestyle choice, for example by not eating meat or any animal-based products, it is not a choice for fish. Certain species require meat, and others don’t. This is largely decided by their environment, as well as specific features such as their mouth, teeth, and digestive tract.

What should you feed a fish?

Fish need proteins, carbohydrates, fats and some minerals and vitamins. The amount of each food type they need depends entirely on the species, and whether they are a carnivore, herbivore or omnivore. Let’s start by looking at carnivores.

1. Carnivores Fish

Carnivorous require a protein rich diet, consisting of plenty of meat in either live or dead form. Species include Piranhas, Cichlids, Arowanas, Bettas, Killifish and Pipefish.

Carnivores typically have a larger mouth with pointed teeth which allow them to rip and tear their prey. They also have shorter digestive tracts and large stomachs when compared to omnivores. Most carnivorous fish are natural predators and enjoy a chase, some are scavengers. In the wild they feast on live fish, insects, larvae and crustaceans.

All fish require some amount of protein; however a carnivore’s diet should be made up of 45% to 70% protein. In addition to proteins, these fish also need some fats to insulate the body, and small amounts of carbohydrates to provide energy.

Carnivorous fish cannot handle or digest large amounts of carbohydrates and so the small amounts of plant matter that they eat will suffice.

To replicate this in your aquarium, you can offer your fish a variety of live and frozen foods.

Recommended Foods for Carnivores Fish

Insects

Blood worms, white worms, tubifex worms and micro worms are available in live and frozen forms and provide good amounts of protein.

Be aware that some worms can carry disease due to the conditions they have been bred in; they should be rinsed thoroughly and observed for a few days in a separate tank before you feed them to your fish.

The beauty about feeding live food is that none of the nutrition is lost, and some live foods such as brine shrimp and micro-worms can be grown at home.

Fish

You can feed your fish a mixture of live, frozen and cooked fish. Some carnivorous fish enjoy hunting and so live fish can be beneficial for them for exercise.

Brine shrimp is one of the best live foods you can feed your fish. Whilst live shrimps can be expensive, frozen brine shrimp is more affordable.

Daphnia are also a popular choice of live food, and whilst not widely available at stores, you can find them at local fish clubs and start breeding your own.

Dried foods and supplements

You can also feed your carnivorous fish a number of dried foods and supplements; you can read more about this in the omnivore section below.

2. Herbivores Fish

Herbivores only consume plant matter; this is more difficult to digest than meats. Their diet includes large amounts of fiber, which is difficult to digest and so they have a longer digestive tract than carnivores.

A herbivorous fish’s diet consists of plants, algae, vegetables and fruits. Unlike a carnivorous fish, they don’t have a true stomach; instead their intestine breaks down the food. For this reason they need to eat more frequently.

They have flat teeth which helps them to grind food before they swallow. Examples of herbivores include surgeonfish and parrotfish.

They are vital in maintaining the ecological balance within coral reefs to keep algae in check.

Recommend Vegetables for Herbivores Fish

Algae and plants

Placing a number of live plants and algae in your tank is a good start for feeding your fish but you shouldn’t rely on these two options alone.

True herbivorous fish tend to suffer in aquariums, because there simply isn’t enough natural plant matter to feed them appropriately if you only give them live plant and algae options.

You should also give them algae wafers to supplement their diet, and flake foods developed for herbivores.

You can feed your fish blanched vegetables such as zucchini, peas, lettuce and spinach.

Vegetables are full of the minerals and vitamins that herbivorous fish need. You can also feed your fish small amounts of fruit including apples and pears..

3. Omnivores Fish

Omnivores consume both meat and plant matter. They possess some of the digestive tract traits of both a carnivore and a herbivore; such as the batfish.

They are possibly the most easy to care for fish, as they will eat a combination of all the suggestions above.

All three categories of fish require vitamins and minerals in their diet to promote healthy growth. Most aquarists supplement their fish’s diet to ensure all the nutritional requirements are met.

What should you feed your fish at home

  • Spinach
  • Lettuce
  • Peas
  • Frozen rice
  • Boiled rice
  • Raw eggs
  • Spirulina
  • Corn and flour
  • Organs and meet (no fat and acidic substances)
  • Fresh seafood
  • Grapes
  • Bananas
  • Freshwater flakes
  • Fluval halagen vegetarian pallets
  • 15 Fluval Bug bites cichlid Formula
  • 16 Repashy super green gel food.