Fish eat a wide range of food from microscopic algae to large fish depending on their environment and diet. Herbivorous fish such as parrotfish feed on micro and macroalgae, and various terrestrial plants such as seagrasses. Carnivorous fish such as sharks and tuna eat small fishes and aquatic animals such as earthworms, sludge worms, brine shrimp, and snails. In an aquarium, fish can be feed with various food available in the form of dry, fried, frozen, and live food.
What can fish eat?
Fish can eat a lot of different variety of food depending on their type of diet and natural ecosystem. In general, the diet of a fish includes food that contains a high amount of fat and amino acids which provide energy and protein for growth.
Fish Food based on the type of diet
Depending on the diet of the fish, the food varies from microscopic plants and algae to large aquatic animals. Fish can be divided into mainly three categories based on their type of diet: herbivore fish, carnivore fish, and omnivore fish.
Diet of an herbivorous fish
The fish which feeds on plants, algae, and photosynthetic bacteria are known as herbivorous fish. These fish can be seen exploring and scraping coral reefs for macroalgae and microscopic plants.
Most of these fishes have teeth infused into a beak-like structure. These teeth are so strong that they can leave scar marks on the rocks.
Herbivorous fishes play important role in a healthy ecosystem by maintaining the balance between corals and macroalgae on reefs.
Most of the algae and plants are have complex cell walls which makes them difficult to digest. Herbivorous fish use mechanical, chemical, or enzymatic means to break down these complex cells to extract the nutrients.
Some common examples of herbivorous fish are surgeonfishes, unicornfishes, saw tails, and parrotfish.
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Diet of a carnivorous fish
Fish that eat meat are known as carnivorous fish. They require more protein in their diet as compared to other herbivorous fishes. Their diet includes earthworms, sludge worms, brine shrimp, snails, water fleas, bloodworms, and feeder fish.
Some large carnivorous fish such as sharks and billfish eat small fish. These fish are also known as predatory fish because of their predator behavior.
These fish typically have strong jaws with long and sharp teeth to catch, hold, and rupture their prey.
Fishes such as Jack Dempsey, perch, muskie, pike, walleye, salmon, sharks, mahi-mahi, billfish, and tuna are examples of carnivorous fish.
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Diet of an omnivorous fish
The fish which feed on both plants and meat are called omnivorous fish. Their digestive tract has the ability to easily break down and extract energy from complex algae cells and meat.
Some of the common omnivorous fish are angelfish, barb fish, buffalo fish, minnows, and sunfish.
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Fish Food based on the surrounding environment
The diet of the fish heavily depends on the surrounding environment. Most of the fishes have evolved over the years to adapt to their surroundings. Most of the fishes can be found either in freshwater (rivers) or saltwater (oceans).
What do fish eat in the ocean?
Fish which live in ocean are known as salt water fish. These fish have adapted themselves to live in high salinity environment of sea.
Fish living in the wild environment of sea can be carnivores, herbivores, or omnivores. The herbivorous fish mainly depend on the algae (both macroalgae and microalgae) and seagrasses while the carnivorous fish eat shrimp, plankton or small crustaceans (crabs, lobsters, crayfish, prawns, and krill).
Some predatory fish such as sharks and tuna fish feed on other small fish and aquatic animals.
What do fish eat in lakes (Freshwater Fish)?
The fish found in river and lakes where salinity is less than 1.05% are known as freshwater fish.
The freshwater fish can also be herbivores, carnivores, or omnivores. Carnivorous freshwater fish includes betta fish, tetra fish, flowerhorn cichlids and afer knife while the herbivorous fish are suckermouth catfish, american flag fish, red bellied pacu and siamese algae eater.
Some common examples of freshwater omnivorous fish are red tail shark, tiger barbs, freshwater angelfish, and barb.
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Diadromous Fish (can live in both freshwater and saltwater)
There are some fish which can survive in both freshwater and salt water. They are known as diadromous fish. They have evolved and developed osmoregulatory mechanisms to survive in different environmental salinities. Examples of diadromous fish are sea lamprey, brook trout and striped bass.
What can you feed fish in aquarium tank?
The diet of fish in the fish tank will depend on your choice of fish. As a beginner, you can have herbivorous fish such as American flag fish or plecos.
There are various variety of foods available to feed herbivorous, and carnivorous fish.
Dry foods: Flake food is artificially created fish food that can be consumed by both freshwater and saltwater fish. There are generally available in the form of pellets, sticks, tablets, granules, and wafers.
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Frozen Food: Frozen food such as shrimp, bloodworms, plankton, and prawn can also be feed to fish.
Freeze-dried: Freeze-dried food such as tubifex worms, mosquito larvae, bloodworms, and water fleas can also be served to tropical and marine fish.
Vacation food: These food blocks items can be feed to fish in case the owner is away from home for a few days.
Live foods: Fish in the aquarium tank can be feed with live foods such as earthworms, sludge worms, water fleas, bloodworms, and feeder fish.
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