Can Celestial Pearl Danio (Galaxy Rasbora) and Electric Blue Crayfish Live Together?

Celestial Pearl Danio (Galaxy Rasbora) 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 Celestial Pearl Danio (Galaxy Rasbora).

Large aggression gap (6 points) between Celestial Pearl Danio (Galaxy Rasbora) and Electric Blue Crayfish increases stress risk for the more peaceful fish.

Celestial Pearl Danio (Galaxy Rasbora) and Electric Blue Crayfish both frequent the Bottom (Substrate) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

There is a critical concern: the Nano / Bite-sized (Predation Risk) behaviour of one fish directly conflicts with the Piscivore (Eats small/nano fish) trait of the other — piscivorous fish will prey on nano-sized tank mates..

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. Shrimp eaters may also prey on very small nano fish.

Worth noting: Electric Blue Crayfish is a known jumper, so a tight-fitting lid is essential.

The safe temperature window for both species falls between 20°C and 25°C. Aim for the midpoint of this range (around 22.5°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 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 6–15 dGH. Regular testing will ensure conditions stay within this range.

To house Celestial Pearl Danio (Galaxy Rasbora) and Electric Blue Crayfish together, plan for an aquarium of at least 75 litres with a minimum length of 60 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 - Densely 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 Celestial Pearl Danio (Galaxy Rasbora)'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.

Celestial Pearl Danio (Galaxy Rasbora) 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.

Feeding time deserves special attention with this pairing. Electric Blue Crayfish is a known shrimp eater and may prey on small invertebrates or nano fish like Celestial Pearl Danio (Galaxy Rasbora).