Chinese Algae Eater (CAE)

Gyrinocheilus aymonieri

Other

Sold widely as a small, peaceful algae-eating juvenile, the Chinese Algae Eater (CAE) undergoes a drastic behavioral and dietary shift as it matures. Growing up to 25cm (10 inches), adults stop eating algae, become highly territorial, and are notorious for attacking slow-moving, flat-sided fish (like Angelfish, Discus, and Goldfish) to feed on their nutrient-rich slime coat. Best kept in fast-flowing river setups with robust, fast-moving tank mates.

At a Glance

Adult Size25 cm
Body ShapeFusiform
Growth RateFast
TemperamentAggressive
Water TypeFreshwater Only
Flow PreferenceHigh
Waste OutputHigh
StockingSolo only

Tank Requirements

Minimum Volume200 L
Minimum Length120 cm
FlowHigh
Water TypeFreshwater Only
Must-Haves in the Tank
Smooth Gravel (Sensitive Barbels)

Water Parameters

Temperature2228°C
pH68
Hardness515 dGH

Temperament & Compatibility

Aggression LevelAggressive
8/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least1 (solo is fine)
Max per Tank1
Can Live Alone?Yes
Behavior Traits
Slime Coat Eater (Attacks Flat Fish)Generally AggressiveTerritorial (Defends specific area)Aggressive to same species/look-alikesHyperactive / Fast Swimmer

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard Adult

The mature, standard-color form. Highly territorial towards its own kind and other bottom-dwellers. Requires a large tank and should absolutely not be housed with slow-moving or flat-bodied fish due to slime-coat feeding.

Differs in 1 trait from base species

Also known as: Wild Type CAE, Adult CAE

Behavior Traits
Slime Coat Eater (Attacks Flat Fish)Generally AggressiveTerritorial (Defends specific area)Aggressive to same species/look-alikesHyperactive / Fast Swimmer

Juvenile (Grow-out)

The common retail size. At this stage, they are relatively peaceful and efficiently consume algae. WARNING: They grow very fast and will transition into aggressive, slime-coat-eating adults.

Differs in 6 traits from base species

Also known as: Baby CAE, Small Algae Eater

Adult Size5 cm
TemperamentPeaceful
StockingNo limit
Min Volume75 L
Min Length60 cm
Behavior Traits
Hyperactive / Fast SwimmerAggressive Eater (Starves shy fish)

Golden / Albino (Adult)

A popular xanthic (gold/yellow) morph. While it looks different, it shares the exact same aggressive behavioral traits, large adult size, and slime-coat-eating tendencies as the wild-type adult.

Differs in 1 trait from base species

Also known as: Golden Algae Eater, Lemon Algae Eater, Albino CAE

Behavior Traits
Slime Coat Eater (Attacks Flat Fish)Generally AggressiveTerritorial (Defends specific area)Aggressive to same species/look-alikesHyperactive / Fast Swimmer

Chinese Algae Eater (CAE) Care Guide Summary

The Chinese Algae Eater (CAE), scientifically known as Gyrinocheilus aymonieri, belongs to the Other family group. Adults reach a maximum size of approximately 25 cm and have a fusiform body shape with a fast growth rate. Classified as aggressive, this species primarily occupies the bottom zone of the aquarium and produces a high level of biological waste.

To thrive, the Chinese Algae Eater (CAE) requires a freshwater only aquarium with a minimum volume of 200 litres and a tank length of at least 120 cm. Water temperature should be maintained between 22°C and 28°C, with a pH range of 68 and a general hardness of 515 dGH. A high water flow is preferred.

Due to its specialist needs, the Chinese Algae Eater (CAE) is best suited for fishkeepers who can provide a carefully planned setup. This species is available in 3 varieties: Standard Adult, Juvenile (Grow-out), and Golden / Albino (Adult). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Chinese Algae Eater (CAE) Habitat Setup

When setting up an aquarium for the Chinese Algae Eater (CAE), a high water flow best suits their natural preferences. Because this species occupies the bottom zone, the aquarium layout should prioritise sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include smooth gravel or rounded substrate to protect their sensitive barbels.

Chinese Algae Eater (CAE) Compatibility Notes

Classified as aggressive, the Chinese Algae Eater (CAE) is best housed alone, as they do not tolerate others of their kind in confined spaces. When choosing tankmates, conspecific aggression can be intense, especially in smaller tanks, territorial behaviour may cause issues if hiding spots or floor space are limited, and their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the bottom zone can help reduce competition and territorial overlap.

Frequently Asked Questions About Chinese Algae Eater (CAE)

How big does Chinese Algae Eater (CAE) get?+
Chinese Algae Eater (CAE) (Gyrinocheilus aymonieri) typically reaches a maximum adult size of approximately 25 cm. They have a fusiform body shape and a fast growth rate.
What tank size does Chinese Algae Eater (CAE) need?+
A minimum aquarium volume of 200 litres and a tank length of at least 120 cm are recommended for Chinese Algae Eater (CAE). This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Chinese Algae Eater (CAE) need?+
Chinese Algae Eater (CAE) thrives in freshwater only conditions with a temperature range of 22–28°C, a pH between 6 and 8, and a general hardness of 5–15 dGH. A high water flow is preferred.
Is Chinese Algae Eater (CAE) peaceful or aggressive?+
Chinese Algae Eater (CAE) is classified as aggressive with an aggression score of 8 out of 10. Careful tankmate selection is essential to avoid conflict.
Can Chinese Algae Eater (CAE) live with others of its kind?+
No. Only one Chinese Algae Eater (CAE) should be kept per tank. Keeping multiples in the same aquarium typically results in aggression and stress.
Does Chinese Algae Eater (CAE) have any special tank requirements?+
Yes. Chinese Algae Eater (CAE) benefits from smooth gravel (sensitive barbels) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

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