Can Celestial Pearl Danio (Galaxy Rasbora) and Discus Live Together?

Celestial Pearl Danio (Galaxy Rasbora) is a peaceful species (2/10), while Discus is generally mild-mannered (4/10). This modest difference means Discus may occasionally assert dominance over Celestial Pearl Danio (Galaxy Rasbora).

Celestial Pearl Danio (Galaxy Rasbora) and Discus both frequent the Middle (Open Water) and 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.

Additional behavioural considerations to keep in mind: Shrimp eaters may also prey on very small nano fish.

There is no temperature overlap between Celestial Pearl Danio (Galaxy Rasbora) (20–26°C) and Discus (28–32°C). This fundamental mismatch makes long-term cohabitation impractical.

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 5–12 dGH. Regular testing will ensure conditions stay within this range. An aquarium test kit is recommended for monitoring.

To house Celestial Pearl Danio (Galaxy Rasbora) and Discus together, plan for an aquarium of at least 300 litres with a minimum length of 120 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: Plants - Densely covered, Sand (Sifters), Driftwood (Digestion/Hiding), Leaf Litter/Blackwater. Meeting these requirements will help both species thrive.

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. Discus is a known shrimp eater and may prey on small invertebrates or nano fish like Celestial Pearl Danio (Galaxy Rasbora).