Pond Algae Eaters (13 Common and Popular Varieties)

Are you worried about algae in your pond? You shouldn’t be, as long as they could be controlled by taking some simple measures.

Having a little algae presence in a pond is good for your pond ecosystem. Because they are the alternative food source for your pond fish and other pond organisms, Pond Algae also produce oxygen and perform photosynthesis activity.

So, having some green algae is fine for your pond, not the blue-green type, though. However, if the algae get out of control, they could destroy the pond ecosystem by consuming all the nutrients from the water and kill all the other pond inhabitants.

There’re some natural ways to keep control or remove algae from pond-

So, how to keep your pond clean from algae?

Introduce algae eaters in your pond. There’s some pond fish that eat algae from your pond. Best Pond Algae Eaters are – Grass Carp, Koi, Pond Loach, Common Pleco, Siamese Algae Eaters, Mollies & Guppies, etc. and Black Japanese Trapdoor Pond Snails.

Using algae eaters in the pond to control the alga outbreak is a simple, easy, and environment-friendly approach. However, if the algae attack is severe, alga eating fish and snails won’t be enough to control them. You have to approach with other methods, that’s another topic.

Therefore, pond algae eaters are best to keep it under control before a severe outbreak. Now, let’s talk about all those common algae eating fish for pond and find out which one is perfect for your pond.

In this article, we’ll discuss about the best algae eating fishes and about a snail. Let’s hop into the list without further ado.

Before talking about the algae eaters, you need to understand some common concepts regarding pond algae and the eaters. Let’s have a look at them:

What Types of Algae fish eat?

Green algae; algae eating fish will feed on the green carpet, hair/string/filamentous algae, blue-green algae, or planktonic algae, which cause the pond water to turn green, especially in a new pond.

Identifying Best Algae Eater for your Pond

Several fish eat algae in a pond, but choosing the right one for your pond is crucial. So, how you choose the right fish for your pond?

To select the right one for you, you must go through some basic information about your pond and the algae eaters.

Size and Depth of the Pond:

Depending on how big and deep your pond is, you can choose the right one. Not all fish can perform best at a big pond. Also, the depth of the pond is important too. Most of the algae eater in this list require around 1000 gallons or more.

Water Temperature:

One of the most critical factors for selecting the best algae eating fish for your pond is water temperature. Some fish are the best suiter for warmer water, while others don’t need that much care about the water temperature.

Warmer region water temperature should be around 70°.

Algae in Your Pond:

What type of algae you have is another dominant factor in choosing the best algae eater for your pond; they have different tastes and choices on eating algae. You have to put those specific according to the algae in the pond.

pH level:

Check the pond’s pH level and use the algae eaters who are okay with that pH level, different pH levels for different fish.

Current Fish in your Pond and other cohabitants:

If you have community fish in the pond, choose another community alga eating fish for the pond. Fighting or territorial fish can attack other fish in the pond. So, pick the right one for the pond.

Pond Algae Eater:

We won’t present all the algae eaters, but the best algae eater for pond. Algae eating fish and snails; will talk about both and try to provide the highest number of algae eaters for your convenience with the detail required for having them in your pond.

What are the common pond algae eater?

Fish and Snails.

What are the Best Algae eating pond fish?

All the mentioned fish below have the descriptions on average fish size, minimum pond size, and pH level; so, before putting an algae eater in your pond, identify these metrics and choose the fish accordingly.

1. Siamese Algae Eater (Crossocheilus oblongus)

Siamese Algae Eater

One of the most common algae eating fish pond is the Siamese Algae eater; it’s a freshwater fish from the carp family.  They are bottom dwellers tropical fish, mainly found in Southeast Asia. Some people got confused them with Flying Fox or False Siamese Algae Eater.

They don’t go well with the smaller or docile fishes like- guppies, smaller catfish, or minnows. Siamese Algae Eater Live around 10 years of age. They will be better with Koi and common Goldfish.

What type of Algae Siamese algae eater eat?

Siamese Algae Eaters are at the top among the most popular algae eaters and happily eat all types of algae in your pond; they are not picky about eating. From string, clumps to red algae, they will almost all types of algae in your pond.

Required water Temperature for Siamese Algae Eater:

It prefers water temperature around 75-79° Fahrenheit or 24 – 26° Celcius.  However, Siamese Algae Eater needs to transfer into an indoor tank during the winter.

Water pH level and hardness for Siamese Algae Eater:

The best pH level is around 6.5-8.0 (7.0 is neutral), and hardiness is around 5-20 dH.

Pond Size for Siamese Algae Eater:

Around 20 gallons or more for a single Siamese Algae Eater, having a wide space is best for this algae eater, as they swim very fast.

2. Koi (aka Nishikigoi) /Cyprinus Carpio

Koi Fish

Most common pond fish around the world. They are also known as ornamental fish, kept in outdoor ponds or gardens. There’re lots of varieties available. Koi Fish is part of the cyprinid family. The oldest Koi was recorded, named Hanako, in Japan. It has lived 226 years before dying in the year 1977.

Apart from their beauty, they can help you to keep your pond clean from algae by consuming. They are not fond of algae, though; if there’s a food shortage in the pond, they will start consuming the pond’s algae and other plants.

So, if you provide less food than usual in a Koi pond, they will start to the algae from the pond.

Required water Temperature for Koi Fish:

Koi are Coldwater fish; however, they will better with 59-77° Fahrenheit or 15-25° Celcius water temperature. Below 10° C or 50° F will affect their health condition; remember this in the winter.

Water pH level and hardness for Koi Fish:

From 7.2-8.0 pH level is best suited for the Koi Fish, and 7.4-8.4 is also good for, they can even live with 6.8-84 level of acidity in the water.

They are hardy fish; Koi will do well in the 9-18 dH or 100-150 ppm.

Pond Size for Koi Fish:

Minimum 1000 gallons are recommended for Koi fish. The recommended requirement for a koi pond is a (6ft x 8ft x 4ft) Six-foot by Eight-foot that is four feet deep.

This will need around 1050 gallons of water for the pond. But you will need a larger pond if you have more fish.

3. Common Pleco (Hypostomus plecostomus)


Common Pleco, also known as suckermouth catfish; However, the original name is Hypostomus Plecostomus is tropical fish. They are not food fish for humans.

In your pond, they will become a good friend for you to keep the pond clean. They scour your pond’s underwater for algae, invertebrates, and crustaceans. A Single adult Plecostomus can consume a considerable amount of string alga. However, it also depends on the amount of food given and the species.

Common Plecos are one of the best algae eaters, whether it’s a pond or aquarium they live in. They can go well with other fish in your pond; Plecostomus is peaceful and friendly.

Required water Temperature for Common Pleco:

65-85° Fahrenheit or 18-30° Celsius water temperature is suitable for plecos; however, 75-82° F or 24-28° C is the best temperature range for most of the plecos. Some plecos can handle some colder water than this too.

Water pH level and hardness for Common Pleco:

A pH level between 6.5-8.0 is acceptable with most of the plecos. But the best is to remain around 7.5.

And the water hardness should be 3-10° dKH (54 to 180 ppm) for the Plecostomus.

Pond Size for Plecostomus:

1000 gallons of water is recommended per Plecostomus in your pond.

4. Channel Catfish (Ictalurus punctatus)

Channel Catfish

North America’s catfish species, they are one of the most fished catfish in the U.S. Channel cat another name for this fish, they are invasive species. They are a bigger fish species among the pond fishes.

Channel catfish are scavenger and omnivore; it’s a well-known bottom feeder fish. They have a very good sense of smell. Catfish will snack heavily on different types of alga from your pond. They’re not the right choice for community fishing. But, surely will help you to keep clean your pond.

Required water Temperature for Channel Catfish:

Water temperature between 75-86° Fahrenheit or 23-30° C is acceptable for Channel Catfish. However, the optimal water condition is around 80° F or 27° C.

Water pH level and hardness for Channel Catfish:

pH level 7.2-8.6 is ok for catfish, and around 7.8 is being considered the best.

Hardiness for Channel Catfish should be between 10-20 ppm.

Pond Size for Channel Catfish:

At least 1000 gallons with 8 feet deep and 3 feet deep sloping edge is recommended for Channel Catfish.

5. Chinese High-Fin Banded Shark (Myxocyprinus asiaticus)

Chinese High-Fin Banded Shark

A popular freshwater aquarium fish, yes, you can have them in your pond too; and obviously, they eat algae since it’s on the list. They are part of the Catostomidae family. But they aren’t suitable for most home aquariums, even though they’re popular among aquarists.

Batfish is another name for this shark, they are bottom feeders, slow grower, and has a very eye-catching figure

Chinese High-Fin Banned Shark grows about 4.5 ft long and consumes algae as one of the main diets, making it the right choice for pond algae control. They are docile and go well with other pond fish.

Required water Temperature for Chinese High-Fin Banded Shark:

Between 60-75° Fahrenheit is a cozy water level for this fish. Below 55° F reduce their activity and movement.

Water pH level and hardness for Chinese High-Fin Banded Shark:

For the High-Fin Banded shark, pH level 6.8-7.5 is suitable and recommended.

And water hardness level in between 4-20 dGH.

Pond Size for Chinese High-Fin Banded Shark:

More than 1000 gallons of water is recommended for High-Fin Banded Shark. Moving and well-oxygenated water is best suited for this algae eater.

6. Pond Loach (Misgurnus anguillicaudatus)

Pond Loach

A freshwater fish from the Cobitidae family; They’re East Asia native fish and popular as pond and aquarium fish. Also known as weather loach.

Pond Loach are bottom-dwelling scavengers, and one of the primary food sources is algae and organic materials of the pond. They are active and peaceful hardy fish, go well with  Koi, Goldfish, and other common pond fish.

Weather Loach also doesn’t need to transfer inside the home during the winter. So, for outdoor or garden pond, they are a good choice for you.

They are opportunistic feeders; if you provide enough food from outside, they won’t bite on the pond algae.

Required water Temperature for Pond Loach:

68-72° Fahrenheit or 20-23° Celsius is a thriving water temperature for Pond Loach, from 65-75° F is okay for them. However, the best thing about the Pond Loach is they do well around 50° F or 13-15° C.

Water pH and hardness level for Pond Loach:

From 6.5-8.0 pH level is sufficient for the Pond Loach. As you can see, they can survive with little acidity with no problem.

Water hardness for Pond Loach is 5-12 dKH.

Pond Size for Pond Loach:

About 50-100 gallons are adequate for the pond loach. So, you don’t have to worried about your pond size.

7. Mollies & Guppies (Poeciliidae)

Molly Fish

With a few algae in your pond and looking for some attractive fish to have in your pond, Mollies and guppies are the right choices for you. As we discussed about Koi, mollies and guppies don’t feed on algae as primary food sources.  Rather, they’re opportunistic feeders.

As long as the other food available, they don’t eat algae. So, if you want to consume your pond’s algae, give less food from outside in the pond.

Guppies and mollies will eat soft green algae from the rocks, pond liner, plants, and other pond substrates. They are can easily take care of and reproduce quickly, so you can sell them to the pet store if you wind up with more than you need.

Required water Temperature for Mollies & Guppies:

For mollies & guppies, 72-82° Fahrenheit or 22-28° Celsius is fair. Since they are tropical fish, warmer water temperature helps them to thrive. During the winter, mollies need to be transferred inside the home.

Required water pH and hardness level for Mollies & Guppies:

For Mollies, pH level 7.5-85 is good. And harness 15-30 dGH.

For Guppies, the water pH level should be between 6.8-7.6. And the water hardness level should be 8-12 dGH.

Pond Size for Mollies & Guppies:

30 and 5 gallons of water for Mollies and Guppies, respectively.

8. Flying Fox (Epalzeorhynchos kalopterus)


Southeast Asian freshwater fish, and part of the Cyprinidae family, and are also known as a green algae eater. Flying Fox is a small fish and will keep nibbling down on the algae from anywhere in your pond. They have an excellent energy level and require more oxygen than others.

A pair of Flying Fox in your small pond can naturally boot the algae. They also will eat the water plants in your pond.

Required water Temperature for Flying Fox:

73-81° Fahrenheit or 23-27° Celsius is the proper water temperature for Flying Fish.

Required water pH and hardness level for Flying Fox:

6.0-7.5 pH level is recommended for Flying Fox.

And water hardness level should be ranging from 2-12 dH.

Pond Size for Flying Fox:

40 Gallons or more water is great for Flying Fox.

9. Goldfish (Carassius auratus)


One of the most popular and well-known freshwater pond and aquarium fish; Goldfish is part of the carp family and native to East Asia. They are omnivores and will indeed feed on the pond algae. There’re lots of varieties of Goldfish available around the world.

Goldfish are similar to Koi fish about eating algae; they will feed on algae, only if the food is scarce. So, if you want to feed on algae, you need to give less food from outside.

Koi and Goldfish will definitely help you to reduce or control algae outbreak in your pond; however, you need to put some alternatives for algae eating in your pond.

Required water Temperature for Goldfish:

60-86° Fahrenheit or 10-30° Celsius is sufficient for Goldfish. The optimal water temperature for them is 68-72° F or 20-22° C.

Required water pH and hardness level for Goldfish:

7.2-7.6 is a thriving pH level for the Goldfish.

And the hardness level for them is around 120 ppm.

Pond Size for Goldfish:

About 500 gallons is suitable for Goldfish in a pond.

10. Otocinclus Catfish (Otocinclus Arnoldi)

Otocinclus Catfish

Otocinclus is a catfish genus and part of the Loricariidae family. They are South American tropical native fish, also known as dwarf suckers. They are considered one of the best algae eaters.

This small fish will happily feed on slimy brown algae and other newly growing algae in your pond; they are good algae eater small pond. Otocinclus go well with community fish. They are not the best suitable for larger ponds, as other big fish could eat them in the pond.

Required water Temperature for Otocinclus Catfish:

72-82° Fahrenheit or 22-28° Celsius.

Required water pH and hardness level for Otocinclus Catfish:

6.0-7.5 pH level is preferred by the Otocinclus catfish, which is a stable pH level.

Water hardness in between 5-15 dH.

Pond Size for Otocinclus Catfish:

The Otocinclus catfish prefer around 20 gallons or more water.

11. Grass Carp (Ctenopharyngodon Idella)

Grass Carp

An Asian herbivorous freshwater fish from the family Cyprinidae;  They are generally large-sized fish for your pond and farmed for eating purpose in the Asian region. They’re an invasive fish and can wreak havoc on the pond ecosystem, as they allowed to breed in there.

Grass Carp will feed on chara (also known as muskgrass), a type of green algae, and won’t consume filamentous algae.

Required water Temperature for Grass Carp:

68-86° Fahrenheit or 20-30° Celsius is the spawn temperature for the Grass Carp.

Required water pH for Grass Carp:

6.5-9.0 pH level is best for Grass Carp.

Pond Size for Grass Carp:

20 Grass Carp for per acre.

12. Black Japanese Trapdoor Pond Snails

Black Japanese Trapdoor Pond Snails

The last one on our algae eater list isn’t a fish; One of the most docile algae eaters for your pond. Black Japanese Trapdoor Pond Snails will feed on loose food and soft algae. They won’t eat your water plants, makes them the perfect choice for your water garden algae eater.

Required water Temperature for Black Japanese Trapdoor Pond Snails:

Around 64-84° F or 12.8-28.9° C.

Pond Size and other water conditions don’t affect much on them. So, you can ignore those parts for them.

Frequently Asked Questions (F. A. Qs)

How do I reduce algae in my pond naturally?

The best way to reduce algae naturally is to add plants to your pond. Plants not just help you to control algae of the pond but also will make your pond more beautiful and enjoyable.

Adding plants to your pond is one of the simplest and long-term solutions to keep the water clear and clean. Lilies and lotus, floating plants, create shade from the sunlight and prevent the algae from receiving sunlight’s nutrition.

Having submerged or underwater plants can produce oxygen like-Hornwort, parrot’s feather, and anacharis, etc.

All those types of plants in your pond will fight for the nutrition available in the water, causing algae to starve and reduce their growth.

You can also use water treatment and high-quality fish food for algae control in the pond. And obviously, you can introduce some algae eaters too.

What Is Algal Bloom?

An algae bloom, also known as the algal bloom, is a fast increase of algae in population or accumulation, whether in saltwater or freshwater. It can easily recognize by the water discoloration from their pigments.

An algal bloom affects the whole ecosystem of your pond or aquarium.

What causes an algal bloom?

The main reason behind the algal bloom is excess nutrients in the water, like- phosphorus, nitrogen, etc.

Is Algae Harmful To Fish?

Controlled and moderate algae in your pond aren’t harmful to your fish or pond either, but they’re a part of the natural ecosystem and improve the overall condition.

However, an excess amount of algae isn’t good for your fish neither for your pond.

Final Say

As you can see, there’re lots of different pond algae eaters out there. Some are the best algae eater for small pond, while some needs more space.

Most of the algae-eating pond fish will go well with other fish in your pond. You don’t have to worry about keeping them together, but you need to consider which type of algae you have in your pond and which algae eater will be best suited for your pond.

Check the water temperature, pH, and hardness level before putting an algae eater in it. However, you can have multiple algae eater types in a single pond, especially when you have opportunistic algae eating fish in the pond like-Koi and Goldfish.

It’s a wise decision to put algae eaters into the work before a severe outbreak. So, consider all the factors mentioned above and choose the best-suited ones for your pond and water garden to keep them clean and fresh.

That’s all for today, guys. See you on another day with different information about your pond, fish, or aquarium. Until then, keep healthy and safe you and your aqua friends. See you!

Now, we want to hear from you-

Which one is the best pond algae eater (according to you)?

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