Can Agassiz's Dwarf Cichlid and Arfak Rainbowfish Live Together?

Agassiz's Dwarf Cichlid is a moderately assertive species (5/10), while Arfak Rainbowfish is peaceful (2/10). This modest difference means Agassiz's Dwarf Cichlid may occasionally assert dominance over Arfak Rainbowfish.

In terms of spatial distribution, Agassiz's Dwarf Cichlid prefers the Bottom (Substrate) zone, whereas Arfak Rainbowfish occupies the Middle (Open Water) and Top (Surface) zones. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

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

Worth noting: Arfak Rainbowfish 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 Agassiz's Dwarf Cichlid and Arfak Rainbowfish 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 24°C and 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

Both fish can tolerate a pH between 7 and 7. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–8 dGH. Regular testing will ensure conditions stay within this range.

To house Agassiz's Dwarf Cichlid and Arfak Rainbowfish 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.

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: Sand (Sifters), Leaf Litter/Blackwater, Driftwood (Digestion/Hiding), Plants - Densely covered, Plants - lighly covered, Smooth Gravel (Sensitive Barbels). Meeting these requirements will help both species thrive.

Agassiz's Dwarf Cichlid prefers Low (Still Water) flow while Arfak Rainbowfish needs High (River/Stream) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.