Species description

Care, breeding and tankmates

Fish profile

Temperament

Territorial

Generally peaceful and industrious, they spend most of their day minding their own business and grazing on algae. They are very active and their constant darting around can sometimes annoy more sedate fish. Older individuals can sometimes become mildly territorial or lazy, preferring prepared foods over algae. Overall, they are considered excellent, peaceful cleanup crew members for the planted community tank.

Diet

Omnivore

Famous for their appetite for algae, they are one of the few species that will eat black beard algae and hair algae. While algae is a significant part of their diet, they are omnivores and must be supplemented with sinking pellets, algae wafers, and blanched vegetables like zucchini. They will also readily accept meaty frozen foods like bloodworms and brine shrimp. A balanced diet prevents them from becoming reliant solely on prepared foods and ignoring algae.

Sex ratio

Group

They can be kept individually or in small groups. When young, they school loosely together, but as adults, they may become slightly territorial with each other. If keeping a group, it is best to have 3 to 5 individuals or more to disperse any potential squabbling. The exact sex ratio is unimportant and difficult to determine anyway.

Feeding frequency

Twice daily

They should be fed once a day with a balanced diet if the tank lacks sufficient algae growth. If there is plenty of natural algae in the aquarium, supplemental feeding can be reduced to a few times a week. It is important to ensure they are getting enough to eat, but overfeeding will cause them to ignore the algae they are meant to clean. Observing their belly fullness can help gauge if they are eating enough.

Bioload

Medium to High

The Siamese Algae Eater has a moderate bioload, as they are active and eat continuously throughout the day. They require efficient filtration to manage their waste output, particularly in planted aquariums where they are often kept. Regular water changes and good tank maintenance are necessary to keep the environment clean. Due to their potential adult size, the bioload increases significantly as they grow.

Flow

Strong

Native to streams and rivers, they appreciate moderate to high water flow and high dissolved oxygen levels. A powerhead or strong filter current simulating a riverine environment keeps them active and healthy. They enjoy swimming against the current and often rest on broad leaves or smooth rocks in areas of higher flow. While they adapt to calmer waters, some current is highly beneficial.

Jump risk

Yes

They are strong, fast swimmers and are notorious jumpers, particularly when first introduced to a new aquarium. A tight-fitting, secure lid is absolutely essential to prevent them from jumping out. Escapes are common if there are any gaps around filter intakes or heater cords. They may also jump if chased by a tankmate or if water parameters become unfavorable.

Reproduction

Impossible (hormone-induced)

Breeding the Siamese Algae Eater in a home aquarium is extremely rare and has rarely, if ever, been documented without hormonal intervention. They are commercially bred in large numbers using hormone injections on fish farms. There are no known specific triggers or conditions to induce spawning in typical aquarium settings. Sexing them is also very difficult, making targeted breeding efforts almost impossible.

Compatibility & tankmates

Community

They are generally peaceful and make great additions to community aquariums with similarly sized, non-aggressive fish. They can be safely housed with tetras, rasboras, gouramis, and peaceful bottom dwellers. However, as they mature, they can sometimes become a bit boisterous or territorial towards their own kind or similar-looking fish like flying foxes. They should not be kept with slow-moving, flat-bodied fish, as they may occasionally attempt to graze on their slime coats.

Tank level

Bottom

They are highly active fish that utilize all levels of the aquarium, but they spend the majority of their time at the bottom and middle levels. They can constantly be seen grazing on the substrate, rocks, driftwood, and plant leaves. They will quickly dart to the surface during feeding time. Providing plenty of surfaces for them to graze on is essential for their enrichment.