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

Reviewed by Guidarium Editorial DeskUpdated April 28, 2026
Not Recommended

Celestial Pearl Danio (Galaxy Rasbora) and Discus are not recommended as tank mates due to no temperature overlap. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Celestial Pearl Danio (Galaxy Rasbora)

Danio margaritatus

Discus

Symphysodon aequifasciatus

🐠Family Group
Celestial Pearl Danio (Galaxy Rasbora)
Cyprinids
Discus
Cichlids - South American
Temperament
Celestial Pearl Danio (Galaxy Rasbora)
Peaceful (2/10)
Discus
Mostly Peaceful (4/10)
Temperature
✗ No overlap
Celestial Pearl Danio (Galaxy Rasbora)
20–26°C
Discus
28–32°C
pH Range
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
6.5–7.5
Discus
5–7.5
Hardness (dGH)
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
5–15
Discus
1–12
Water Type
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
Freshwater Only
Discus
Freshwater Only
Flow Preference
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
Low
Discus
Low
Min Tank Volume
Combined: 250 L
Celestial Pearl Danio (Galaxy Rasbora)
38 L
Discus
250 L
Swimming Level
Shared: 2 zones
Celestial Pearl Danio (Galaxy Rasbora)
MiddleBottom
Discus
MiddleBottom
🏷️Behavior Tags
Celestial Pearl Danio (Galaxy Rasbora)
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)
Discus
Shy / Slow Moving (Easily Stressed)Territorial (Defends specific area)Aggressive to same species/look-alikesShrimp Eater
Stocking calculator

Can your tank handle Celestial Pearl Danio (Galaxy Rasbora) and Discus?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Celestial Pearl Danio (Galaxy Rasbora)
Discus
Test both in my tank

Behaviour & Temperament

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.

Water Parameters

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.

Tank Setup

To house Celestial Pearl Danio (Galaxy Rasbora) and Discus together, plan for an aquarium of at least 250 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 - 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.

Why This Pairing Usually Fails in Practice

Celestial Pearl Danio (Galaxy Rasbora) and Discus 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.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Celestial Pearl Danio (Galaxy Rasbora) and Discus.

Show 1 more tank size

Diet & Feeding

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).

Frequently Asked Questions

Can Celestial Pearl Danio (Galaxy Rasbora) and Discus live together?

No. This combination is not recommended. Key incompatibilities — such as non-overlapping temperature ranges — make cohabitation unsafe.

What size tank do Celestial Pearl Danio (Galaxy Rasbora) and Discus need?

A minimum of 250 litres (tank length at least 120 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Celestial Pearl Danio (Galaxy Rasbora) and Discus together?

Unfortunately, there is no temperature range that satisfies both species. Celestial Pearl Danio (Galaxy Rasbora) requires 20–26°C, while Discus needs 28–32°C.

Are Celestial Pearl Danio (Galaxy Rasbora) or Discus aggressive?

Celestial Pearl Danio (Galaxy Rasbora) is peaceful (2/10) and Discus is generally mild-mannered (4/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Celestial Pearl Danio (Galaxy Rasbora) and Discus need?

Both species overlap in the 6.5–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

How do I manage Discus's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Discus space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
April 28, 2026
Last updated
April 28, 2026
Issues or corrections?
Contact the editorial team

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