Herbivorous Freshwater Fish: Interesting Facts

The world of fish is divided into carnivores, omnivores, and especially herbivores. The plant-friendly species are the easiest ones to raise since they can adapt well to life in an aquarium tank. 

However, you still need to know some core features and characteristics of herbivorous freshwater fish to raise them properly. What to feed herbivorous fish? What are their ideal temperature range and living conditions? 

I will discuss everything about herbivorous fish and give you interesting information on these species. Keep reading to find out!

Most Popular Herbivorous Freshwater Fish 

Herbivorous fish species are an indispensable part of a beautiful aquarium ecosystem. However, not all fish are plant eaters and have different behaviors or living tendencies. 

Here are some prominent examples of herbivorous freshwater fish. Since they are all plant-shredder, putting these fish in a natural aquarium environment rather than a plant-based tank is advisable. 


Goldfish are not entirely herbivorous but voracious omnivores. They will look for vegetarian food when their stomach isn’t full after a meal. 

In the wild, goldfish hunt crustaceans and worms by hiding in the substrate. This tendency is maintained even when you raise goldfish in an aquarium tank. 



Mbuna’s main food is the algae attached to the lakebed in wildlife. Similar to goldfish, Mbuna is only partly herbivorous, but they will consume any plant. 

Aquarium keepers usually stock the Mbuna tank with a lot of plants and algae to reduce their aggressive nature from attacking the other fish. An excellent choice of plant for Mbuna tanks is Anubias, but the fish will still nibble this plant. 


Oscars is a very popular cichlid fish from South America, with high intelligence and a noticeable individual awareness. Though Oscars are not herbivorous, it still tends to destroy small plants and decorations. 

Due to its high awareness, Oscars think of themselves as the main decoration of the tank. So, they will shred and destroy any plants smaller than their sight. 


Pleco is not suitable for life in aquarium tanks due to its large size and clumsiness. A mature Pleco can reach between 18 and 20 inches in length (around 45 to 50 centimeters). 

The fish will destroy and nibble any plants using its sucker mouth. In addition, Pleco is a nocturnal fish that only hunts at night, while in the day, it spends most of the time hiding. 


Most tetras species can adapt well to planted aquarium tanks. They regularly hide and dash in vegetal thickets as a shelter, and tetras love to swim in schools. 

While some tetras love a diet of insects, meaty stuff, and fry, the other tetras’ species only feed on vegetal food.

The most noticeable example is Buenos Aires, which is an excellent candidate for your aquarium tank.

buenos aires tetra

What Do Herbivores Eat? 

Herbivore fish only feed on plant-based matters and food, which should be high in fiber. Some excellent food for herbivore fish diet is 

  • Algae: Algae is the main food source for herbivorous fish in wildlife, but you can still grow it in your aquarium tank. 
  • Fruits: some ideal fruits are peas, apples, bananas, and plantains, which are rich in fiber and vitamins. It would be best if you shredded them into tiny pieces before feeding the fish. 
  • Plants And Vegetables: Prioritize fiber-rich and easy-to-digest veggies such as zucchini, lettuce, and spinach. 

The food is processed by their long guts and intestines since herbivores don’t have real stomachs. Therefore, they have to graze the food constantly with their flat teeth before swallowing it.

In wildlife, herbivores play a critical role in maintaining the natural ecosystems of algae and coral reefs. Without them, coral reefs cannot absorb natural sunlight due to the widespread algae on their surface. 

However, not all herbivores eat plant-based food. Some species are only partly herbivorous, and they still incorporate a little meat and protein-rich stuff.

Herbivorous Fish Are Vital To Coral Reef Ecosystems


What Freshwater Fish Don’t Eat Plants?

The majority of freshwater fish are plant eaters, but some species could be better for a plant-based aquarium tank. Some of the worst species to avoid are Buenos Aires tetras, silver dollar fish, scats, and even goldfish. 

Some large fish, like the Leporinus genus, can mature very quickly, and they tend to destroy tank plants.

What Fish Can You Put Together In A Freshwater Tank?

Some freshwater species, like knife fish, cichlids, or loaches, don’t share the same tank space with their related kinds. Here are some recommended combinations of fish species to put in a freshwater tank. 

  • Green Neon Tetra and Apistogramma Dwarf Cichlid.
  • Synodontis Catfish and African Cichlids
  • Tiger Barbs and Rainbow Shark 

Why Are Herbivorous Fish Important?

Herbivorous fish species are a critical part of many coral reefs and aquarium ecosystems. They help maintain a balance between macroalgae and corals.

The corals need natural sunlight to grow and survive, which is blocked by algae. 

Without herbivorous fish to eat the algae, the corals cannot survive and will significantly affect the coral reef ecosystems. 

Do Herbivorous Fish Have A Stomach?

No, herbivorous fish don’t have a real stomach in their digestive system. They have a long gut responsible for digesting most vegetable food. 

Their digestive tract has a curved and straight tube shape with a glandular lining. 

How Do You Feed Herbivorous Fish?

Herbivorous fish’s favorite food is fresh algae, dried algae, and frozen food for fish. Their diet revolves mainly around vegetal components. However, you need to ensure that the food supply is always available at any moment.

Final Thoughts

Not all herbivorous freshwater fish can adapt well to an aquarium tank, even though they mainly feed on vegetal food.

Therefore, you should be careful when choosing herbivorous fish to prevent them from ruining the tank’s ecosystem. 

Diversifying the diet of your herbivorous fish with veggies, fruit, and nutritious stuff is essential for their growth and well-being. You should also keep fish with different living habits and tendencies in separate tanks. 

I hope the examples and information relating to herbivorous fish can satisfy you.

Thank you for reading!