The 19 Best and Most Effective Algae-Eating Fish for Outdoor Ponds

Fish ponds are mentioned in documents from the Middle Ages. In actuality, the nobles retained them as a symbol of their dominance. Originally built to supply fish for food, fishponds functioned as a regulated reservoir for many civilizations. Moreover, water gardens date back more than 3,500 years, when the Egyptians used water piped from the Nile to their own private gardens where they raised papyrus and lotuses and kept fish.

In the present day, anyone may construct a garden pond and fill it with a variety of lovely plants and fish to enjoy thanks to advancements in construction techniques and materials. Furthermore, adding fish that consume algae to a pond is advantageous for the fish as well as the pond. As a reference tool, we have examined the top 19 algae-eating fish for outdoor ponds.

While some fish species primarily eat algae, others like a mixture of insects and other food sources. Fish should not be overfed, too, since this can lead to an overabundance of algae and add more matter to the pond than the fish will consume. Before adding pond fish to a body of water, it is imperative to educate oneself about the various species of pond fish that exist, as well as their mature size, temperament, and acceptable water temperature. Some pond fish, for instance, are reticent to be noticed, but others like doing so and will amuse the observer as they glide over the water. The size of the pond and the climate in which the top 19 best and most efficient algae-eating fish for outdoor ponds will reside should be taken into consideration.

Why Does Algae Grow in Outdoor Ponds?

Aquatic habitats are home to a variety of algae, some of which are just natural development while others may be a sign of issues with the fish or the pond’s health. For instance, because they are an excellent provider of food and oxygen, green and string algae maintain a healthy ecology. Excessive amounts of either type of algae might cause oxygen imbalances, which could endanger or kill the fish. Long-term sun exposure will also accelerate the growth of algae and cause fish to overfeed.

Ponds should ideally be placed in shady spots away from trees to avoid any issues with falling leaves. Algae can spread quickly due to poorly maintained filtration systems. Always keep the pond clean of trash, leaves that have fallen, and anything else that can decompose in the water. This will boost the growth of algae, disrupt the ecosystem’s chemical balance, and put the fish living there in risk.

An ideal habitat for fish and plants can be ensured by being aware of the beneficial and dangerous kinds of algae. Overabundance of algae will cause issues and must be thinned down. Additionally, an imbalance in the pond’s chemical composition could lead to an increase in algae development, which could be dangerous for the fish. High concentrations of nutrients in the water, such as phosphorus or nitrogen, which are brought on by the following, are other causes of excessive algal growth:

Animal waste in the pond
Urban runoff
Septic systems

Pond weeds can grow in ponds and can be manually removed with a skimmer or rake. Make use of a weed cutter for those that take root.

The 19 Greatest and Most Powerful Fish for Outdoor Ponds That Eat Algae

Selecting the proper fish for a pond is crucial to keeping algae under control. As a result, the top 19 algae-eating fish for outdoor ponds are as follows:

Japanese koi
Grass carp
Dojo Loach
Nerite snail
Bullfrog tadpole
Molly fish
Japanese trapdoor snail
Siamese algae eater
Channel catfish
Apple snail
Chinese algae eater
Flying fox
Gold nugget pleco
Chinese high-fin banded shark
Shubunkin goldfish

Japanese Koi (Cyprinus rubrofuscus)

Carp and Japanese koi are related. In actuality, they were domesticated in the 19th century by Japanese rice growers. Koi are referred to as Nishikigoi in Japan. This translates to mean the “swimming jewel,” signifying luck, prosperity, and good fortune. They can be black, orange, white, or any combination of these; they can even occasionally be blue in hue. Koi can reach lengths of two to three feet and weights of up to 35 pounds. They eat algae, plants, and water insects as a favored food. Every year, they procreate, depositing their eggs on aquatic vegetation and other items that are submerged. They have a 40-year lifespan on average. Nonetheless, some claim that one lived to be a ripe old age of 230 years! Since they are prone to sunburn, provide them with a covered space.

Goldfish (Carassius auratus)

Originating in East Asia, the Chinese domesticated this relative of the koi. They can reach a length of 10 to 12 inches, have an average lifespan of 10 to 15 years, and eat insects, debris, other invertebrates, and algae in addition to other plants. When the temperature is 40 degrees Fahrenheit (4.4 degrees Celsius) or higher, they grow well in outdoor ponds.

Grass Carp (Ctenopharyngodon Idella)

This huge fish is endemic to East Asia and belongs to the minnow family, which also includes koi and goldfish. Grass carp can reach a maximum length of 5 feet and a maximum weight of 40 pounds. As a result, smaller ponds should not consider them. Their color is greenish-brown, and they have a characteristic “fishnet” pattern due to the big black or dark brown scales and silvery sides. Grass carp may devour up to three times their body weight each day and will feed on a wide range of aquatic plants, including those that eat algae. Grass carp are bred for food in China.

Dojo Loach (Misgurnus anguillicaudatus)

This native of East Asia fish resembles a whiskered eel and is also called a weather loach or pond loach. They can reach a maximum length of 10 inches and are colored gray, albino, pink, or orange, among other hues. This fish feeds on the bottom and enjoys eating tubifex worms, small aquatic invertebrates, and algae. These gregarious fish approach humans at the side of the pond, where they are frequently fed by hand.

Otocinclus (Otocinclus)

These little fish are indigenous to South America and are related to catfish. They are 1.5 to 2 inches long on average. They’re also known as dwarf suckers or otos because of their long, narrow bodies with a horizontal stripe. These fish are special because they can breathe air. This happens as a result of their stomach and esophagus’s junction adapting. They like to devour other plants and algae.

Nerite Snail (Neritina natalensis)

This little, skilled eater of algae only lives for a year. They are indigenous to Africa and have a size range of.5 to 1 inch, with occasional sizes up to 1.5 inches. Also referred to as Spotted Nerite Snails, Tiger Nerite Snails, and Zebra Nerite Snails, these snails are a beautiful addition to any pond because of their variety of patterns and colors!

Plecostomus (Hypostomus Plecostomus)

A few species of Plecostomus, a member of the catfish family, are the common pleco, rhino pleco, and spotted pleco. Also called the catfish with a suckermouth. While the various species varies in size, they all average around 20 inches in length and have a lifespan of 10 to 15 years.The albino bristlenose pleco, which is around 5 inches long, is a smaller variation of the pleco. Their preferred foods are algae, detritus, and occasionally newly hatched snails, insects, small fish, and small crustaceans, along with lettuce, cucumber, or zucchini. This tropical fish can actually breathe air because it is native to South America. Their surroundings affect their coloration, which can range from dark brown to a sandy hue with black dots. They live in dark cracks during the day and are nocturnal.

Bullfrog Tadpole (Lithobates catesbeianus)

A bullfrog tadpole’s larval stage can endure anywhere from a few months to three years. They eat algae, mosquito larvae, aquatic plants, and a few invertebrates during this time. Their life cycle consists of an egg, a tadpole, a tadpole with legs, and an adult bullfrog, which has a lifespan of seven to ten years. Since adult bullfrogs dislike algae, they will seek out alternative food sources. They have dark dots and can be light to dark green in color. They are endemic to the southern, eastern, and midwestern regions of the United States.

Mosquitofish (Gambusia affinis)

This tiny, freshwater fish native to North America is between 1.5 and 2.5 inches long, with the female being the larger member of the species. They actually give birth to living children. They will consume insects, small invertebrates, plants, especially algae, and mosquito larvae, thus their name. They may also consume hundreds of mosquito larvae in a single day.

Molly Fish (Poecilia sphenops)

This fish, which is native to Mexico and Colombia, is between two and five inches long and is available in a number of colors, including silver, black, white, golden, and dallatine. They easily multiply and give birth to living offspring.

Japanese Trapdoor Snail (Viviparis malleatus)

Originating from East Asia and North America, these sizable freshwater snails can reproduce asexually and have colors ranging from dark green to brown to black. They will consume decaying plants in addition to their insatiable appetite for algae. These are live-bearing snails that can reach a maximum length of two inches as adults. They can withstand low temperatures. But since they can become invasive in the wild, it’s crucial to keep them contained.

Siamese Algae Eater (Crossocheilus oblongus)

Southeast Asia is the original home of this lovely freshwater carp. They enjoy eating algae, fresh vegetables, and vegetable debris. Their sleek, long bodies are either gold or gray with a wide black horizontal stripe that extends from the head to the tail. They will live for roughly ten years and reach a maximum length of six inches. They do not, however, take well to cold water.

Channel Catfish (Ictalurus punctatus)

These fish, which are native to North America, can weigh up to 40–51 pounds. They can grow up to 4 feet in length, however they often measure 16 to 24 inches. They work best on larger ponds and have a lifespan of about 15 to 20 years. Channel catfish actually have taste buds all throughout their bodies, with the majority of them being near their gills and whiskers. Grayish-blue in hue, they have a black back and a white belly. The albino mutation might give them a peach-colored appearance. These bottom-dwelling organisms enjoy both algae and aquatic plants and insects.

Apple Snail (Ampullariidae)

Native to the West Indies, Central America, and South America, these snails are amphibious. They are, nevertheless, prohibited and intrusive in several US states. One type that can be found in the US is the Mystery Snail. They are the largest freshwater snails on the earth, growing up to 5.9 inches in length and displaying a spectrum of hues from bright yellow to brown, blue, or light pink. They can also harm non-food pond plants because they enjoy eating algae and dead or living plant materials. They want water that is between 70 and 80 degrees warmer.

Chinese Algae Eater (Gyrinocheilus aymonieri)

They are also known as sucking loaches and honey suckers; they are native to Southeast Asia. They are sold as food in local marketplaces. They are excellent additions to ponds since they are herbivores that enjoy eating algae. They have a solid stipe or spots, and range in hue from olive to pale grey. They are 6 inches long. Chinese Algae Eaters are simple to maintain and love warmer water.

Flying Fox Fish (Epalzeorhynchos kalopterus)

These stunning fish, which are native to Southeast Asia, like warmer waters. They and the Chinese algae eater are frequently confused. They live for eight to ten years and have an average size of 4.7 inches. They are olive green to dark brown in appearance, with a black line running from the mouth to the tail. Their diet is completed by vegetables, crabs, aquatic insects, tubifex worms, and algae—with the exception of red algae.

Gold Nugget Pleco (Baryancistrus xanthellus)

This native Brazilian fish, which belongs to the catfish family, has black and yellow spots and inhabits the Amazon River. They adore eating algae and can reach a length of 12 inches. They also have a pleasing appearance.

Chinese High Fin Banded Shark (Myxocyprinus asiaticus)

This massive fish, which can reach a length of 4.5 feet, is indigenous to China. Entsuyui (Japanese for “Chinese banded shark”), Siamese sucker (Chinese emperor), rough fish (Hilsa herring), freshwater batfish (freshwater batfish), wimple (Wimple carp), Chinese sucker, Asian sucker, topsail sucker, sailfin sucker, Chinese high-fin sucker, high-fin loach, banded loach, high-fin, or Chinese sailfin sucker are some other names for it. They have a large, triangular dorsal fin and a brown body with three black, slanted stripes surrounding it. They live for about twenty-five years. They enjoy eating algae and are herbivores that can survive in cold water between 55 and 75 degrees Fahrenheit (12 and 23 degrees Celsius).

Shubunkin Goldfish (Carassius auratus)

Shubunkin goldfish, which are native to Japan, are a mix between a common goldfish, a comet goldfish, and a calico telescope eye. They resemble koi fish. Their silvery bodies are speckled with black and orange. There are three types: the Bristol, London, and American. Their body forms and fin configurations vary. Blue is actually the most valuable color. They will reach a maximum length of 9–18 inches and live for 10–15 years. Algae is their favorite food. This fish can withstand cold conditions very fine.

For the 19 Greatest and Most Powerful Algae-Eating Fish for Outdoor Ponds, How to Maintain a Clean and Healthy Pond

Using a pond vacuum to remove dirt from the bottom and a skimmer to gather leaves, clean the pond on a regular basis.

Installing a net over the pond to trap neighboring tree leaves and shield it from predators would help you manage the nearby vegetation.

Cultivate plants that float, lilies, marginals, wetlands, and oxygenators. Take care that they don’t completely cover the area.

In winter, manage the ice to avoid decreased temperatures in the pond and decreased oxygen levels below the surface. To let in sunlight, de-ice, put a translucent cover, or add a heater.

Reduce the amount of sunlight that algae receive by planting lilies to control the growth of algae. Algaecides are harmless for fish and aquatic plants and will control algae growth.

By removing obstructions, flushing debris, and partially cleaning the biological filter to prevent killing beneficial bacteria, you can maintain the pump, filter, lines, and fountains. Algaecide and cleaning chemicals are also used to remove algae blooms and limescale.

Investigate and fix leaks, which can be indicated by dropping water levels or by the presence of moisture in the immediate vicinity.

Keep the water level at the proper level; otherwise, warmer weather may cause the pond’s oxygen content to diminish. Crucially, it needs to be inspected frequently all summer long.

Use a heater to keep the temperature at the ideal level throughout the winter, when ice may form. Water temperatures can rise over the summer, but this can be avoided by adding more cold water to the pond to lower the temperature.

To make a pleasant water garden, keep it well-aerated to benefit both plants and animals, lessen the formation of algae, and get rid of odors. Air-moving features like waterfalls, bubblers, and fountains will increase the amount of oxygen in the water, as will oxygenating plants. For air levels, an air pump will also be helpful.

Chlorine and other substances can disrupt the ideal water chemistry and cause the death of aquatic life. Actually, decomposing plants can also change it. Acidic and poisonous situations will be managed by detoxifiers and alkaline solutions. In actuality, edging might assist in resolving issues with water runoff.

In summary

In addition to providing a sense of peace to a garden, outdoor ponds can attract valuable wildlife. Although maintaining a pond involves some work, the benefits are well worth the effort. Outdoor ponds are a common focus point in landscape design, and when illuminated, they take on a dramatic quality. Ponds actually serve as havens for a number of animals, including dragonflies, which spawn and consume mosquitoes, salamanders, newts, damselflies, and other birds. Incorporate natural plants to offer refuge and nourishment for all garden inhabitants.