Can Boeseman's Rainbowfish and Electric Blue Crayfish Live Together?

Boeseman's Rainbowfish is a peaceful species (2/10), while Electric Blue Crayfish is semi-aggressive (8/10). This notable difference means Electric Blue Crayfish may occasionally assert dominance over Boeseman's Rainbowfish.

Large aggression gap (6 points) between Boeseman's Rainbowfish and Electric Blue Crayfish increases stress risk for the more peaceful fish.

In terms of spatial distribution, Boeseman's Rainbowfish prefers the Top (Surface) and Middle (Open Water) zones, whereas Electric Blue Crayfish 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.

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

There is no temperature overlap between Boeseman's Rainbowfish (26–30°C) and Electric Blue Crayfish (18–25°C). This fundamental mismatch makes long-term cohabitation impractical.

Both fish can tolerate a pH between 7 and 8.1. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 9–15 dGH. Regular testing will ensure conditions stay within this range.

To house Boeseman's Rainbowfish and Electric Blue Crayfish 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, Sand (Sifters), Driftwood (Digestion/Hiding). Meeting these requirements will help both species thrive.

Note a potential conflict in setup requirements: Electric Blue Crayfish is a plant destroyer, which conflicts with Boeseman's Rainbowfish's requirement for live plants. Compromise where possible or prioritise the more critical need.

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

Boeseman's Rainbowfish and Electric Blue Crayfish are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.