Siamese Algae Eater

Siamese Algae Eater

Siamese Algae Eater is a small, beautiful, and energetic freshwater fish having silvery black color. Besides its beauty to glitter your aquarium, it is pretty much handy for aquarists to clean algae’s growth in the tank. They are an ideal candidate for community tank because of their peaceful behavior, lower cost, tiny size, moderate care level, and simple food requirements.

Siamese Algae Eater

Siamese Algae Eater (SAE) is a freshwater fish found in rivers and streams of Southeast Asia. Its natural habitat is the bottom of freshwater sources in Indonesia, India, Malaysia, and Thailand.

They belong to the family Cyprinidae that is the same as that of Minnows and Carps. They are popular amongst aquarists for their particular attraction to algae.

They can clean the aquarium for some types of algae like black brush algae, red algae, black beard algae, and thread algae. 

These types are otherwise laborious to get rid of from other remedial measures. Other algae eater having an almost similar physical appearance that of SAE are available in the market. 

This article will discuss the Physical characteristics of Siamese Algae Eater, their resembled counterparts, their habitat, lifespan, food requirements, water quality parameters, aquarium settings, and other related features.   

Siamese Algae Eater Profile

Attributes Siamese Algae Eater
Family Cyprinidae
Scientific Name CrossocheilusSiamensis, CrossocheilusOblongus
Other Names True Siamese Algae Eater
Natural Habitat Southeast Asia, Malay Peninsula
Size Max size 6 inches
Lifespan ten (10) years
Care Level Intermediate
Breeding Level Difficult
Tank Size 30 gallons for a pair
Temperature 70°F-79°F
pH 6.5-7.5
Hardness 4-12 dGH
Alkalinity (kH) 5.0-10
Nitrites 0
Nitrates <50 ppm
Ammonia 0
Food Group Omnivorous
Tank Mates Other peaceful pets (African Butterfly Fish, Tetras, Gourami, Guppies, Rainbowfish, livebearers, barbs, rasboras, Mollies, African Shrimps, Danios)
Colors Greyish brown, brownish, black-edged scales, silvery-white bottom
Salient Features slender body, long body, a black striped line from nose to the end of the tail
Specialty Only Red Algae Eater

Scientific Name and Family Profile

First, They kept them in the genus Epalzeorhynchus having their previous scientific name of EpalzeorhynchusSiamensis.

Later on, they assigned them their present genus that is Crossocheilus. It is because of the presence of barbels on its upper lips. Therefore, its accurate and current scientific name is CrossocheilusSiamensis.

Another species found in JAVA has the scientific name CrossocheilusOblongus accepted in Indochina and Sundas Island. However, this name is not very common for them in the aquarium trade.  

Reason for Name

Siamese algae eater takes their name due to two reasons. The first part of their name owes to their presence in rivers and streams in Thailand (Formerly known as Siam). The second part is due to their appetite for algae.

They can unstoppably eat different algae species. They have an unconditional appeal for red hair algae and brush algae that other algae eaters don’t like. 


They have a long, slim, and streamlined body having a trademarked black stripe running horizontally from the tip of their mouth to the end of their caudal fin.

Edges of this black band are in a zig-zag pattern that is a feature used to differentiate them from their resembling species. However, that difference is visible when the fish reaches a size of 3-4 inches.

They have transparent fins. The bottom of the fish is shiny white color. The upper body has a greyish brown or brownish look. It has four thin barbels on the upper lip to detect food items. 

Females are slightly plumper than males. It is the only description to distinguish males from females.   

Fish of Cyprinidae Family Resembling Siamese Algae Eater 

There are four other fish that have a very close resemblance to Siamese Algae Eaters. In the first look, they are all similar. However, they have minute differences.

It is essential to differentiate the True Siamese algae eater from these false algae eaters as they are the only red algae eater.

Those four species are:

● False Siamese Algae Eater (Garrataeniata)

● The Flying Fox (Epalzeorhynchuskalopterus)

● Crossocheilusoblongus

● Chinese Algae Eater (Gyrinocheilusaymonieri)

The chart given below presents some of the minute differences amongst these five fish to differentiate them from each other.

  True Siamese Algae Eater            False Siamese Algae Eater            The Flying Fox      Crossocheilusoblongus           
Black Horizontal Band Zig-zag edges

From nose to end of the tail

Smooth edges

Up to base of the tail


Smooth edges

From nose to end of the tail but broader and darker at the tail

Smooth edges

Up to base of the tail

Fins Clear   Black bands, plain or dark edges for Anal and Dorsal Fins,

Yellowish for Pelvic fins

Transparent front and black edges            Translucent
Mouth Small suckermouth Small, suckermouth, non-clinging

bright red or pink lips

Small suckermouth Small suckermouth
Barbels 04 04 04 04

Natural Habitat

They live in the freshwater sources of southeast Asian countries like India, Thailand, Malaysia, Borneo, Southern Myanmar, and Indonesia.

They like water sources having high currents like streams and rivers. They are bottom feeders and use the sand and gravel surface of these water bodies as their substrate.

The presence of plantations in their habitat is a plus point for their growth and rest. They prefer shallow, clear waters with plenty of algae growth. They migrate to deep and turbid water during harsh weather conditions.  


They can live for 8-10 years if proper care, food, and water quality are maintained. In the wild, they can even live longer due to the variety of food and quality of their natural habitat.


It can grow up to a size of 6 inches. Juveniles are available in pet stores in sizes 1-¼” inches to 2-½” inches according to their age. It takes about two (02) years for them to reach their maximum length.

Why Do Siamese Algae Eaters Rest on Plant Leaves?

They have a specific rest position different from other fish that lie on their bellies in the tank. They support up their body on their tail, pelvic and pectoral fins in a standing position. 

They need broad-leaved plants in the aquarium as their babies and young ones like to rest on them. Adult fish rest on thick, low plants near the tank floor.

Furthermore, in the absence of a developed swim bladder, they remain in a continuous motion to avoid sinking. They cannot stand still or rest in the water. Otherwise, they fall like a dead object.

Can they live alone or in groups?

They are freshwater dwellers in constant swimming in the aquarium. They prefer to live in small schools. However, you can keep a single piece or any other numbers according to your aquarium requirements as their primary purpose is to control algae growth in the tank.

It is a safe practice to purchase only females as there can be competition amongst males to attract females. However, it is not mandatory because they cannot hurt each other or any other pet in the aquarium during these fights.

Siamese Algae Eater Diet

Siamese Algae Eater fulfills a large part of their diet by eating algae on the aquarium plants and surface. However, they belong to the group of Omnivorous vertebrates.

They can consume all types of food items. Moreover, Feed them with other commercial fish food items like sinking flakes and pellets. You can also add live food items containing insects, worms, and phytoplankton to their diet.

They can consume fish fry and dead matter they find. They also like chopped fruits and blanched vegetables like peas, Zucchini, and lettuce.

How Much and How Often to Feed Siamese Algae Eaters?

Their primary function in the tank is to eliminate the Red Algae. Therefore, you should keep the number of other food items limited to maintain their appetite for algae.

Some aquarists have observed that they stopped eating algae after they become habitual of provided foods. 

Feed them once per day with the quantity of food worth 3-4 minutes of eating. It is sufficient for their nutritional requirements.

They are the Only Red Algae Eaters Available

Siamese Algae Eaters are the only fish to eat red algae or black brush algae. Its talent to graze on this specific type of algae first discovered in the 1970s in Europe.

Since then, it has gained popularity, and aquarists adopt a small group of 2-4 of this algivore to control the algal growth.

How to Make Black Algae Suitable for Siamese Algae Eaters?

Low amounts of CO2 in the tank make the black algae hard and un-appetizing for this fish. Therefore, introduce controlled amounts of Carbon Dioxide in the aquarium or soak the aquarium plants with hydrogen peroxide.

It will make algae softer and weak suitable for them. You will observe an increase in their algae grazing rate with these steps.

Other Types of Algae that SAEs can Eat

Besides red algae, they can devour other algae types such as green dust algae, brown film algae, microalgae, red slime algae, and green thread algae. 

Siamese Algae Eaters Breeding

They are difficult to breed at aquariums. Most of them are available in the aquarium trade are either produced at large farmhouses using hormones or captured as baby fish from their natural habitat in the wild that are rivers and streams.

They have slight differences from their relatives that have a resemblance to them. They are not distinguishable at a young age. Therefore, there are chances of getting some other species instead of “True Siamese Algae Eater” when purchasing it from a pet store. 

Cost of adopting siamese algae eater as a pet

They are pretty much inexpensive to purchase and keep as a pet. Baby fish are available at pet stores at a nominal cost of %3 to $5.

Usually, they are kept as a side pet with other colorful fish to facilitate the tank cleaning from algae.

Therefore, they are a pretty much economical choice to keep as a pet at your aquarium. Moreover, they validate their expenditure by keeping the tank clean.  

Are They Aggressive?

They are peaceful creatures and don’t harm or fight with any other fish in a community tank. Male fish can compete and chase each other to attract females towards them. However, they don’t bite or injure in these fights. 

Care Level of the fish

They have no special requirements as far as food and other tank conditions are concerned. Therefore, they require a moderate care level to maintain their health and growth rate.

Any beginner aquarist can take them as a pet with a lower investment. 

Water quality requirements

They are freshwater dwellers. They need clean water with some specific water quality parameters.

Although they can survive some harsh water conditions, it is mandatory for their growth and keeps them happier.

Optimal water parameters are pH value in the range 6.5-7.5, a value of 5.0-10, and temperature value from 70℉-79℉. Use a heater to maintain the temperature range.

General hardness in the range of 4-12 dGH is required. Water should be Ammonia and Nitrite free. The nitrate level should be less than 50ppm. Use a circulation pump to produce flow in the aquarium water.

Aquarium size requirements

They are active swimmers and need plenty of green plants for their ideal environment. Therefore, an aquarium size of 30 gallons is sufficient for a pair of them.

However, keep on increasing 10 gallons per further addition of individual fish. Keep the tank length larger than height to have an open swimming area.  

Plantation: They need plenty of broad-leaved and shallow plants in the aquarium to match their natural habitat. They are also required to fulfill their food requirements. Moreover, they also prefer to rest on these plants and leaves.

Substrate: Tank substrate should contain sand or round pebbles to avoid hurting them due to a hard, rough layer of gravel as they are bottom feeders. They also like logs or rocks in the tank as their hiding places.

Lighting: They don’t have special requirements as far as lighting is concerned. Moderate lighting for 12 hours to provide as per day and night cycle is sufficient for them. Expose the tank to moderate sunlight to promote algae growth to fulfill a part of their dietary requirements.

Oxygenation: Freshwater inhabitants prefer rich oxygen for efficient breathing. It is also beneficial for their colors’ enhancement and growth. Installation of air stones and vegetation in the tank will provide for this requirement.

Tank Cover: They are very active and energetic fish. They can jump out of the aquarium. Therefore, use a lid to avoid them moving out of the tank.

How to add Siamese Algae Eater to New Aquarium?

Acclimation is a process to avoid any abrupt changes in the original water conditions in which the pet comes from the pet store. Introduce pets through a slow process to their new aquarium.

The two acclimatization techniques available to add them to your aquarium are the floating and the drip method. The drip method works best for this fish.

Carefully add small amounts of water to the original pet water to keep the water parameters constant. Perform this process slowly to avoid any abrupt water quality changes. The optimal time to complete the acclimatization is one hour.

Can They Live with Betta Fish?

Betta fish are aggressive and fight with other fish having similarities in their appearance or interfere in their zones. Therefore, it is not a wise choice to keep Siamese Algae Eaters with Betta fish.

Tank Mates

They are peaceful creatures and can live with a variety of other non-aggressive fish in harmony. Examples of some bottom feeders to be in the same tank are loaches and Catfish. 

They can also live with African Butterfly Fish, Tetras, Gourami, Guppies, Rainbowfish, livebearers, barbs, rasboras, Mollies, African Shrimps, and Danios.

Pets to avoid keeping with a Siamese algae eater

Avoid putting aggressive and territorial species of fish as they can attack these peaceful algae eaters.

One such example is the Red-Tailed Shark that shares natural habitat with this fish. Another example is Red Devil Fish because they are territorial and aggressive fish.

Avoid keeping them with spawning fish as they are active swimmers and can hinder or stress the spawning fish. One such example is Dwarf Cichlid. 

Final Words:

Siamese Algae Eater is a peaceful fish ideal for community tanks to clean the excessive algae growth. It is the only algae eater that can eat red algae or black hair algae.

Moreover, their hardy nature, low cost, and easy care level make them an ideal candidate for beginners to add to their community tank.