10 Best Algae Eaters For Freshwater Aquarium

Algae Eaters For Freshwater Aquarium

Keeping algae out of your aquarium is an essential activity that takes a bit of time to get right. Other than using the regular glass scrapers and shaving blades to scratch the algae from the aquarium walls, there is another well-used method.

This method uses fish, snails or shrimps to take care of the ever-growing algae. Algae is like a treat for them, and it also serves as a food source in case of emergency.

Below is a list of the best fish, snails, and shrimps for removing algae from your aquarium.

You should also check this API ALGAEFIX Algae Control (Link to Amazon), its really helpful! 

Best Fish for Eating Algae

1. Siamese Algae Eater

Siamese algae eaters are one of the best fish for removing algae, as they feed on a range of different kinds of algae. They are also useful for removing some of the types of algae that other algae-eaters will avoid.

This species is also rather quiet and relatively easy to look after, so are good for beginner aquarists looking to control the algae in a new tank.

Siamese Algae Eater

Siamese algae eaters need a tank that is at least 30 gallons in size, and prefer a pH of 6.5 to 7.0 and a temperature of 75°F-79°F.

These fish can be housed in community tanks and can be cared for moderately easily, as long as they have sufficient algae for food. It’s not a bad idea to add algae wafers or pellets to their diet, to ensure they’re not starving.

2. Chinese Algae Eater

Chinese Algae Eaters are easy to care for and are good in tanks with a capacity of at least 30 gallons. However, these fish grow quite large–up to ten inches–and become increasingly aggressive. Therefore, be careful not to keep them in a tank full of delicate fish.

Chinese Algae Eater

Their aggression can be a good thing, on the other hand, as they are one of the only algae eaters who can share a tank with large and semi-aggressive fish such as cichlids.

The Chinese Algae Eaters prefer a pH from 6.8 to 7.4 and a KH from 8 to 10. Their preference is for warmer temperatures, and they are herbivores.

They are not one of the most effective algae eaters, because they tend to become quite lazy as they get older, but while they are still young they are quite useful at feeding on different types of algae. They also need hiding places such as hollow logs or rock caves.

3. Twig Catfish

These fish have long, thin bodies and are about 4cm long. Twig Catfish are docile, so are compatible with peaceful species such as tetras and livebearers, although cichlids and bigger fish may intimidate them.

Twig Catfish

While they were once fairly unusual, the more aquarist hobbyists learn of their benefits, the more these fish become increasingly available. These fish are best kept in pairs and require a tank that holds at least 12 gallons.

They prefer moderately soft water with a pH from 6.0 to 8.0 and changes in water chemistry are not taken well. They feed on most types of algae but still need some additional food. The Twig Catfish does need more specialized attention compared with other algae-eaters. They also need hiding places in the tank because they are very shy.

4. Otocinclus Catfish

The Otocinclus Catfish (also called dwarf suckers and Otos) is another catfish on our list. The main advantage of adding otos to your aquarium is that they are quite small, enabling them to fit into smaller spaces and reach the algae in harder to reach spots. Otos seldom grow over 2 inches long. However, don’t let their tiny size fool you – they can eat an unbelievable amount of algae!

Otocinclus macrospilus

Dwarf Suckers  will eat all kinds of vegetation and algae, but they prefer brown algae and soft, green algae. However, it must be noted that otos have a large appetite, therefore you need to make sure that they have enough food available.

Otos are a schooling fish and should be kept in groups of at least 5, unlike the previously mentioned Twig Catfish and Siamese Algae Eaters. However, as they are quite small, you don’t need a large tank, and 30 gallons is more than enough.

Otos usually live happily with most fish species, but bear in mind that Cichlids and Angelfish are known to attack them as they are so small.

Best Alge Eating Snails

5. Nerite Snails

Nerite Snails are one of the most popular algae eaters. It’s no wonder that these little gems are so popular, with their beautiful zebra stripes and their enormous appetite for algae.

Nerite Snails eat every type of algae, including the algae that is harder to eradicate from freshwater aquariums such as Green Spot and Green Beard Algae. They also live at the bottom of your tank and can help to keep the substrate clean.

Nerite Snails are easy targets for large predatory fish, such as Cichlid and Loaches, measuring around 3cm when fully grown, so we do not advise keeping them with aggressive fish.

Nerite Snails prefer a pH level of 7 or higher. They also need hard water, as the calcium will keep their shells hard and healthy.

The only problem with these snails is that if you don’t keep it covered, they tend to climb out of the tank. Hundreds of little white eggs are also left around your tank, sometimes fully covering the plants. This is great if you are actively trying to breed the snails, but otherwise the eggs are a bit of an eyesore.

Nerite Snails are a great small algae eater and we definitely recommend them, even with these two small problems.

6. Apple Snail

The Mystery Apple Snail is on the opposite end of the snail spectrum to nerite snails. They can grow to be as big as a baseball, so make sure you have sufficient tank space to accommodate them.

Apple Snails

Mystery Snails can be spotted easily, not only because of their size but also because of their huge antennas. Their shells are usually bright yellow but are also sometimes brown, violet or red.

Mystery Apple Snails are mostly used to eat algae, substrata algae, and aquarium glass algae.

Usually, you will find them eating the substrate algae, while also collecting any food residue. They have good appetites, and even though they will eat most types of algae, we still recommend that you to feed them with a wide range of aquarium safe vegetation.

Larger Mystery Snails are normally safe, but smaller ones are often targeted by larger predatory fish. They also tend to eat your live plants, once they’ve consumed all the algae, so be sure they are well fed. In conclusion, if you can get your hands on it, the Mystery Apple Snail is an excellent addition to any tank.

7. Trumpet Snail

The Malaysian Trumpet Snail is once again a very small snail. These busy algae-eaters only grow to about 2cm when fully grown, and will keep your aquarium nice and clean.

They consume all kinds of algae as well as any remaining vegetation and food. The Malaysian Trumpets don’t eat your plants (unlike the Mystery Apple Snails) so they are ideal if you’d like to include live plants in your aquarium.

In order to keep their shells nice and hard, they prefer alkaline water.

During the day and during the night, when they are busy, you will find Malaysian Trumpet Snails digging their way across the substratum, consuming all material and algae that have fallen through the cracks.

Malaysian Trumpets are very susceptible to predators, due to their size, so be careful not to keep them with predatory fish.

Best Agle Eating Shrimps

There is a wide variety of aquarium shrimp species available, including Cardinal Shrimp, Crystal Red Shrimp, Amano Shrimp, Arlequin Shrimp and Red Cherry Shrimp.

8. Cardinal Shrimp

Cardinal Shrimps are remarkable in having a lot of white dots on their bodies that make them very spectacular. Originally, they came from Indonesia, more specifically from Sulawesi, a place where several other well-known shrimp species also originated.

With regard to the most appropriate aquarium water temperature, we recommend that it does not fall below 25°C.

Also, it is good to know that both the pH and the water hardness should not be higher than seven or eight percent, otherwise the shrimp will not thrive. You can use coral fragments to increase water hardness, or even fine sand, to reproduce the natural conditions in which Cardinal Shrimp live.

This species feeds especially on algae, such as spirulina. Alternatively, you can try food designed for invertebrates, as it has high algae content. It is said that the best time to feed the cardinal shrimp is when it’s dark, because they do not like eating when it’s too light.

In addition, you do not need to feed them more than once a day, and there’s no need to panic if you forget to feed them for two or three days in a row, as they will consume the debris from previous meals.

Interestingly, male and female Cardinals can be told apart by the presence of an egg storage pouch, which occurs only in females. This can only be seen with an infrared lamp. Cardinal Shrimps reproduce in fresh water. A female can lay up to 15 eggs, and their young will hatch within a month.

As far as their behavior is concerned, Cardinal Shrimps are very active and always trying to find sources of aquarium food. They are not aggressive at all, and will tolerate many species of aquatic life. They are particularly happy to share a tank with Sulawesi Snails because they would share their natural environment with them.

9. Crystal Red Shrimp

Crystal Red Shrimps are easy to look after, have a beautiful color and are highly sought after. However, they can cost as much as 50 euros, so you need to be prepared!

Crystal Red Shrimp

Crystal Red Shrimp appeared recently in the ’90s when someone from Japanese crossed a few specimens of the typical Albina Shrimp (with black and white stripes) with some that had red stripes instead of black ones. The result was the appearance of several classes of Crystal Red.

Generally, these shrimps prefer less acidic water, with a pH below seven percent and a hardness of five. It is best that the water temperature does not get above 28°C.

When they reach maturity, female Crystal Red Shrimps are slightly larger than the males. Females have a space under the belly, where they will store the fertilized eggs until they are hatched.

Crystal Red Shrimps are easy to reproduce and multiply with ease. At birth, youngsters are minuscule, not exceeding 2mm.

In terms of feeding this shrimp species, they consume algae. Therefore, it is advisable to give them this aquarium food.

Crystal Red Shrimps will eat all food debris that has not been consumed by other creatures in your aquarium and, above all, they adore cooked carrots or squash. All this must be cut into pieces no bigger than 2mm or 3mm.

In order not to risk damaging the water quality, if the vegetables are not consumed within a day, they need to be taken out of the water. Moreover, keep in mind that you do not have to feed these shrimps too much food, because they do not eat very much. The food scraps increase the level of nitrates in the tank, damaging the quality of the water.

10. Amano Shrimps

Amano Shrimps are the second most popular shrimp, after the Red Cherry Shrimp.

It is very difficult to reproduce in an aquarium, so the vast majority of specimens come from the wild. However, over the last few years and with much effort, several copies have been reproduced.

Amano Shrimp

Amano Shrimps are very sensitive, often dying within a few days of being introduced to an aquarium. The main reason for this is the stress and fatigue caused by their journey from their natural environment to the aquarium. They also need feeding properly.

Besides the algae in the aquarium, they also need other sources of food, such as pumpkins, cucumbers, boiled spinach or specially designed food.

As with all shrimp species, do not forget to remove the vegetable residue after 24 hours to keep the water quality at its best.

If you are wanting to breed Amano Shrimp, it is good to know that this species needs water with a very low salinity, better known as salty water.

Once the chickens hatch, there are larvae that climb through the aquarium, unlike other shrimp species that give birth to live chickens.

Also Check: Amano Shrimp vs Ghost Shrimp

It is advisable to keep these shrimps in an aquarium of at least 150 liters. The pH must be neutral and the temperature in the water should not be less than 24-25°C.

Amano Shrimp females will produce anything from a few hundred to a few thousand eggs. After five weeks, the larvae will come out of them. It is contraindicated to move the females into salt water before the larvae appear, because the eggs will not hatch.

Larvae of Amano will thrive in 10-liter aquariums. You need to keep in mind that you need a water salinity of around 30-35 ppm and a temperature of about 25°C.

How to Control the Aquarium Algae

Growing algae is a fact of life that every aquarium owner will face sooner or later. Some algae are normal and healthy, but excessive algae growth can be dangerous for fish and plants alike.

Types of algae

Do you already have algae in the aquarium and want to get rid of it? Knowing the type of algae will determine the cause and also the remedy. We will present types of algae, and how to get rid of them.

Brown algae, also known as Gravel or Silica algae. Frequently in new aquariums, this will cover the aquarium in layers that can be easily removed. It is usually harmless and will eventually disappear as the aquarium is maturing.

Blue-green algae, also known as Slime or Smear algae – caused by excess nitrates and phosphates, is a cyanobacterium. It can spread rapidly and can cause considerable damage. Good water care will help, but if the water source has phosphates in it, it may be necessary to use special treatments to eliminate excess nutrients. Erythromycin is also effective against blue-green algae.

Red algae or Beard algae – This is the most difficult algae to deal with, and usually occurs on plants. A bath in a low bleach solution (5% to 10%) for a few minutes will often kill this type of algae.

Green algae, also known as Hair, Fillet or Spot algae – This is a normal type of beneficial algae that each aquarium will most likely have to some extent. As long as the aquarium is well cared for, it will not cause any problems.

Green Water, also known as Algae Bloom – This is caused by the growth of microscopic algae that are suspended in water. It is one of the most frustrating types of algae to eliminate because it cannot be scraped like other algae.

Generally, water exchanges are not effective, as the remaining algae will grow rapidly. Using a diatomic filter or blocking all the lights for a few days is usually required to remove green water.

What Causes Excessive Algae Growth?

Like any plant, algae need three elements to grow: water, sunlight, and nutrients. If an excess of any of these is available, algae will grow rapidly and start to cause a problem.

Obviously, you cannot go without water in the aquarium, but you can control the amount of light and nutrients in the water. Here are the common reasons for excessive algal growth.

  • Lights – Excessive photoperiod and inadequate spectrum
  • Aquarium is placed in a location with direct sunlight
  • Water exchanges
  • Using water with high nutrients

Tips for Algae Prevention

Knowing the causes of algae growth is the half the battle. Here’s what you need to do to avoid excessive algal growth.

Reduce lighting – Do not place the aquarium where there is direct sunlight, even for part of the day. Sunlight can and will promote the growth of algae. When using artificial light, make sure it is not stronger than necessary and is on for no more than eight hours a day. Make sure you use a timer to turn the lights on and off every day.

Less food – Most aquarists will over-feed, which leads to increased levels of phosphate in water. Feed small portions and watch the fish eat it all. If the food is not eaten in five minutes, always remove any debris.

Water changes – The most important way to avoid algae is to make regular water changes. Replace ten to fifteen percent of aquarium water every week to keep nutrients low.

Know Your Water – Test your water source. If it is rich in phosphates, you should consider using phosphate removal or find another source of water. It is also good to test nitrates as some water sources have increased nitrates.

Algae Removal – If you see that algae grows on glass, on stones or on other hard surfaces in the aquarium, remove them. Wipe the glass, remove the stones and clean them and vacuum the gravel when making water changes.

Keep your plants alive – Living plants use many of the nutrients which algae needs in order to develop. Fewer nutrients mean that there is less food for the growth of the algae.

Clean up Crew – introduce algae-eating animals and fish.

Algal Control in the Aquarium

Algae cannot be completely eradicated as it lives in almost any environment and travels as spores through the air, and is therefore able to reach the aquarium at any time. The important thing is to know the correct methods for preventing excessive algal growth.

Algae can be controlled by restricting its access to all the elements necessary for its development, thus it’s an idea to maintain an aquarium with strong illumination but with little nutrition or vice versa.


This is one of the essential elements of algae development, and is found in the aquarium as ammonia, nitrite and nitrate. The level of nitrogen concentration in the aquarium can be controlled by limiting fish food, limiting the number of fish and making partial water changes weekly.

The light

This is the most common cause of excessive algae development in an aquarium, be it sunlight or too much artificial light, and it contributes decisively to the growth of algae. It is recommended to keep the aquarium out of direct sunlight because in almost all cases it starts algal development.

In the case of planted aquariums where artificial light is used, it is recommended that, at the first signs of algal growth, you increase the number of fast-growing plants and add floating plants that will limit the amount of light that will penetrate the water.


These chemical compounds accumulate in the aquarium due to excess animal waste. A high concentration of phosphates is likely to occur in aquariums where fish are fed excessively or in an overpopulated tank.

It is also possible that tap water extracted from the upper layers of the phreatic soil contains a high concentration of phosphates, from agricultural fertilizers that have been applied in the surrounding fields. There are several filtered environments that can be used to fix this problem.


Over-fertilization in the aquarium is another common cause for the excessive growth of algae, and this can be remedied by adding more plants and establishing a balance between algae and plant development.

Related Questions

Are algae eaters aggressive? This depends on the species. For example, Siamese Algae Eaters and Betta fish tend not to get along, because the SAE fish likes to bite the Betta. This is due to the Betta’s large fins and tails which are very attractive to the SAE!

Are algae eaters good to have? Yes. They do a good job by helping you keep the algae under control.

Will algae eaters clean my tank? You should not rely solely on the algae eaters to get rid of algae from your tank. They will do their job and limit the spread of algae and keep it under strict control, but it’s still up to you to do regular water changes and aquarium cleanups.

Are Plecos good algae eaters? This depends on what species of Plecos we are talking about. Most plecos will not touch algae since they are bottom dwellers and they only clean the bottom of the tank by eating remaining food and other fish waste.

Saurabh Kumar

I am a passionate fish keeper, with years of experience. You will find some really useful tips and information on this blog about Freshwater Aquariums.

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