Can Apple Snail and Clown Killifish Live Together?

Apple Snail is a peaceful species (0/10), while Clown Killifish is peaceful (2/10). This modest difference means Clown Killifish may occasionally assert dominance over Apple Snail.

Apple Snail and Clown Killifish both frequent the Top (Surface) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Aggressive eaters may outcompete shy fish for food, leading to malnutrition.

Worth noting: Clown Killifish is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 23°C and 27°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

The pH requirements of Apple Snail (7.2–8.5) and Clown Killifish (5–7) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 8–8 dGH. Regular testing will ensure conditions stay within this range. An aquarium test kit is recommended for monitoring.

To house Apple Snail and Clown Killifish together, plan for an aquarium of at least 180 litres with a minimum length of 90 cm. This accounts for the larger species' space requirements with an additional 20 % buffer to reduce territorial tension.

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: Established Algae (Otocinclus), Shells (Breeding/Hiding), Plants - Floating, Plants - Densely covered, Leaf Litter/Blackwater. Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Apple Snail is a plant destroyer, which conflicts with Clown Killifish's requirement for live plants. Compromise where possible or prioritise the more critical need.

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

Feeding time deserves special attention with this pairing. Apple Snail is an aggressive eater that may prevent Clown Killifish from getting enough food.

Because Apple Snail is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Clown Killifish receives an adequate share.