Can Australian Smelt and Chinese Algae Eater (CAE) Live Together?

Australian Smelt is a peaceful species (1/10), while Chinese Algae Eater (CAE) is semi-aggressive (8/10). This notable difference means Chinese Algae Eater (CAE) may occasionally assert dominance over Australian Smelt.

Large aggression gap (7 points) between Australian Smelt and Chinese Algae Eater (CAE) increases stress risk for the more peaceful fish.

In terms of spatial distribution, Australian Smelt prefers the Top (Surface) and Middle (Open Water) zones, whereas Chinese Algae Eater (CAE) occupies the Bottom (Substrate) zone. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

There is a critical concern: the Shy / Slow Moving (Easily Stressed) behaviour of one fish directly conflicts with the Slime Coat Eater (Attacks Flat Fish) trait of the other — slime coat eaters target slow-moving fish, causing severe stress and health issues..

Additional behavioural considerations to keep in mind: Aggressive fish may bully and stress shy, slow-moving species. Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Australian Smelt is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 22°C and 24°C. Aim for the midpoint of this range (around 23.0°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 8. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–15 dGH. Regular testing will ensure conditions stay within this range.

To house Australian Smelt and Chinese Algae Eater (CAE) together, plan for an aquarium of at least 200 litres with a minimum length of 120 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.

Specific environmental needs for this combination include: Plants - lighly covered, Smooth Gravel (Sensitive Barbels). Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.