Siamese Algae Eater

 Quick Care Facts

• Care Level: Moderate   • Temperament: Peaceful   • Maximum Size: 6"
• Minimum Tank Size: 30 gallons   • Water Conditions: 75-80° F, KH 5-10, pH 6.0-7.0
• Diet: Omnivore   • Origin: Southeast Asia   • Family: Cyprinidae
• Species: Suckermouth Catfish   • Aquarium Type: Community

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Native to the many tributaries, streams and drainage ditches of Southeast Asia, the Siamese Algae Eater (Crossocheilus siamensis) is a schooling species of suckermouth catfish. They are found living amongst the dense vegetation along the banks and bottoms of the many streams and drainage ditches of the tropical areas of Southeast Asia. Generations spent living in an environment of dense aquatic vegetation has made the Siamese Algae Eater a master at eating algae from all manner of plant leaves, stalks and stems, which consequently has endeared them with those who keep planted aquariums the world over.

Often referred to as the "friendly" algae eater, the Siamese Algae Eater (Crossocheilus siamensis) has a lot more going for it than simply being more peaceful than the more widely available and similar in appearance Flying Fox (Epalzeorhynchus kalopterus) and the Chinese Algae Eater (Gyrinocheilos aymonieri). It is due to the similarities in appearance between these species, that hobbyists will often refer to the Siamese Algae Eater as the True Siamese Algae Eater in order to more clearly distinguish it from the more common Flying Fox and Chinese Algae Eater, who are often mislabeled as a Siamese Algae Eater.

Although Siamese Algae Eaters are a bit more rare than their Chinese cousins, they are readily available within the hobby and do great in peaceful planted community aquariums. Their peaceful temperament and effectiveness at eating a wide variety of algae types has endeared this species with planted aquarium hobbyists the world over. In fact the Siamese Algae Eater is one of the few species of suckermouth catfish that is known to consistently feed on Black Brush or Black Beard algae.

The Siamese Algae Eater, although dull and not colorfully attractive, can be an important asset when dealing with various forms of algae and is also an intriuging schooling fish, ideal for community setups. Their ideal tank setup would mimic their southeast Asian streams; however, they will also do well in planted tanks and general larger community aquariums. As is the case with most species originating from streams and rivers, they need additional water flow via a power head or canister return and plenty of dissolved oxygen.

In their native stream habitats they are accustomed to clean, flowing water and plenty of room for schools of individuals to swim about. They prefer aquarium setups that have at least moderate water flow and plenty of plants and rock on which they can graze for algae and adequate size to accommodate at least 6 full grown specimens. Ideally this species should be kept in a 4 foot long, 55 gallon or larger aquarium which will provide enough swimming room for a group of 6 or more 6 inch adult True SAEs.

When kept in small groups the Siamese Algae Eater is very peaceful towards tank mates and will generally school about the aquarium feeding on algae with its mates. However, if not kept in a small group or school they will tend to act like Barbs who are not kept in groups and nip at other fish. This occurs because they are used to living in a group and the fish within the group will communicate their position to others in the group by slightly touching or nipping each other as they move about the aquarium. Fish who aren't accustomed to living in schools will find this behavior to be stressful.

Proper tank mates vary from community fish species like Tetra, Barbs, Corydoras, Gouramis, Loaches, Rasboras, Rainbowfish and peaceful Cichlid species. The key is keeping a small group of Siamese Algae Eaters and keeping them with fish who are not large or aggressive enough to see them as food. They make an excellent compliment to most community aquarium setups as they control algae growth and swim in attractive looking schools.

It is well known within the aquarium hobby that the True Siamese Algae Eater is a prolific consumer of algae, including some species of algae like Black Beard Algae that many other algae eaters won't consume. Algae will most often make up the bulk of this species diet, much to the joy of hobbyists looking to control algae growth within their tanks. However, if there is a shortage of algae in the aquarium the True SAE will gladly consume a wide variety of commercial foods including flakes, freeze-dried worms and shrimp, algae wafers and even vegetables like zucchini or green beans.

Despite having some distinct differences in body shape, coloration and pattern, the Siamese Algae Eater is continually mislabeled as a Chinese Algae Eater (Gyrinocheilos aymonieri) or a Flying Fox (Epalzeorhynchus kalopterus).

Lets start with the easy one first, the Chinese Algae has some very distinct differences between itself and the true Siamese Algae Eater (SAE). These differences include: much larger, thicker and longer body; larger and more down turned suckermouth; rounder and thicker head; dark brown coloration and brown spotted pattern on the top of their body and lastly a brown lateral stripe instead of the very black stripe of the SAE.

Now for the more challenging part, identifying a True Siamese Algae Eater from the False Siamensis and Flying Fox fish. The most apparent difference between them is the horizontal black stripe running the length of the body. Both the False Siamensis and Flying Fox have a sharp, smooth black stripe topped with a gold stripe. The True Siamese Algae Eater has a lateral stripe that has ragged edges between the black stripe and the gold body coloration. Additionally, the Flying Fox has red and black on its finnage, which becomes very pronounced as they become adults.

Another distinction between the SAE and the False SAE and Flying Fox is the number of pairs of barbells on the mouth of the fish. True Siamese Algae Eaters have a single pair of barbells (whiskers) by their mouth; where as, False Siamensis and Flying Fox have two pairs of barbells. While this difference can be more difficult to see on small fish darting about in an aquarium, it can definitively identify which species it is.

Lastly, the behavior of the fish can help identify their true identity. True Siamese Algae Eaters are a schooling species who will stay together with others of their own kind, both swimming and feeding in small groups of individuals. While both the False Siamensis and Flying Fox are solitary species who will attempt to claim a territory and prevent other suckermouth catfish from entering by chasing off any of their own or similar species of fish.