Can Gardner's Killifish and Monster Wolf Fish (Aimara) Live Together?

Gardner's Killifish is a generally mild-mannered species (4/10), while Monster Wolf Fish (Aimara) is highly aggressive (10/10). This notable difference means Monster Wolf Fish (Aimara) may occasionally assert dominance over Gardner's Killifish.

Large aggression gap (6 points) between Gardner's Killifish and Monster Wolf Fish (Aimara) increases stress risk for the more peaceful fish.

Gardner's Killifish and Monster Wolf Fish (Aimara) both frequent the Middle (Open Water) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

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

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Gardner's Killifish and Monster Wolf Fish (Aimara) to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

The safe temperature window for both species falls between 23°C and 26°C. Aim for the midpoint of this range (around 24.5°C) for optimal comfort.

Both fish can tolerate a pH between 6 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 4–10 dGH. Regular testing will ensure conditions stay within this range.

To house Gardner's Killifish and Monster Wolf Fish (Aimara) together, plan for an aquarium of at least 1500 litres with a minimum length of 240 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

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

Gardner's Killifish prefers Low (Still Water) flow while Monster Wolf Fish (Aimara) needs High (River/Stream) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Gardner's Killifish and Monster Wolf Fish (Aimara) need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.