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

Reviewed by Guidarium Editorial DeskUpdated May 4, 2026
Not Recommended

Celestial Pearl Danio (Galaxy Rasbora) and Domino Synodontis are not recommended as tank mates due to piscivorous fish will prey on nano-sized tank mates.. 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

Domino Synodontis

Synodontis notatus

🐠Family Group
Celestial Pearl Danio (Galaxy Rasbora)
Cyprinids
Domino Synodontis
Catfish
Temperament
Celestial Pearl Danio (Galaxy Rasbora)
Peaceful (2/10)
Domino Synodontis
Semi-Aggressive (6/10)
Temperature
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
20–26°C
Domino Synodontis
22–26°C
pH Range
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
6.5–7.5
Domino Synodontis
6–7.5
Hardness (dGH)
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
5–15
Domino Synodontis
4–18
Water Type
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
Freshwater Only
Domino Synodontis
Freshwater Only
Flow Preference
✓ Compatible
Celestial Pearl Danio (Galaxy Rasbora)
Low
Domino Synodontis
Moderate
Min Tank Volume
Combined: 250 L
Celestial Pearl Danio (Galaxy Rasbora)
38 L
Domino Synodontis
250 L
Swimming Level
Shared: 2 zones
Celestial Pearl Danio (Galaxy Rasbora)
MiddleBottom
Domino Synodontis
MiddleBottom
🏷️Behavior Tags
Celestial Pearl Danio (Galaxy Rasbora)
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)
Domino Synodontis
Piscivore (Eats small/nano fish)Aggressive to same species/look-alikesTerritorial (Defends specific area)Hyperactive / Fast Swimmer
Stocking calculator

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

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)
Domino Synodontis
Test both in my tank

Behaviour & Temperament

Celestial Pearl Danio (Galaxy Rasbora) is a peaceful species (2/10), while Domino Synodontis is moderately assertive (6/10). This notable difference means Domino Synodontis may occasionally assert dominance over Celestial Pearl Danio (Galaxy Rasbora).

Celestial Pearl Danio (Galaxy Rasbora) and Domino Synodontis 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.

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: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Water Parameters

The safe temperature window for both species falls between 22°C and 26°C. Aim for the midpoint of this range (around 24.0°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 5–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Celestial Pearl Danio (Galaxy Rasbora) and Domino Synodontis 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, Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding). 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 Domino Synodontis 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 Domino Synodontis.

Show 1 more tank size

Frequently Asked Questions

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

No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.

What size tank do Celestial Pearl Danio (Galaxy Rasbora) and Domino Synodontis 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 Domino Synodontis together?

Keep the aquarium between 22°C and 26°C. A target of around 24.0°C sits comfortably within both species' preferred ranges.

Are Celestial Pearl Danio (Galaxy Rasbora) or Domino Synodontis aggressive?

Celestial Pearl Danio (Galaxy Rasbora) is peaceful (2/10) and Domino Synodontis is moderately assertive (6/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Celestial Pearl Danio (Galaxy Rasbora) and Domino Synodontis 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 Domino Synodontis's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Domino Synodontis 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
May 4, 2026
Last updated
May 4, 2026
Issues or corrections?
Contact the editorial team

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