Can Black Phantom Tetra and Scarlet Badis Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 1, 2026
Possible with Caution

Keeping Black Phantom Tetra and Scarlet Badis together is possible but requires caution due to potential behavioral clashes. Provide a spacious tank of at least 60 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Black Phantom Tetra

Hyphessobrycon megalopterus

Scarlet Badis

Dario dario

🐠Family Group
Black Phantom Tetra
Characins
Scarlet Badis
Other
Temperament
Black Phantom Tetra
Peaceful (2/10)
Scarlet Badis
Mostly Peaceful (3/10)
Temperature
✓ Compatible
Black Phantom Tetra
22–28°C
Scarlet Badis
18–26°C
pH Range
✓ Compatible
Black Phantom Tetra
5–7.5
Scarlet Badis
6.5–8.5
Hardness (dGH)
✓ Compatible
Black Phantom Tetra
1–15
Scarlet Badis
4–20
Water Type
✓ Compatible
Black Phantom Tetra
Freshwater Only
Scarlet Badis
Freshwater Only
Flow Preference
✓ Compatible
Black Phantom Tetra
Low
Scarlet Badis
Low
Min Tank Volume
Combined: 60 L
Black Phantom Tetra
60 L
Scarlet Badis
20 L
Swimming Level
Shared: 1 zone
Black Phantom Tetra
Middle
Scarlet Badis
MiddleBottom
🏷️Behavior Tags
Black Phantom Tetra
Nano / Bite-sized (Predation Risk)Hyperactive / Fast SwimmerShy / Slow Moving (Easily Stressed)
Scarlet Badis
Nano / Bite-sized (Predation Risk)Shrimp EaterFry PredatorShy / Slow Moving (Easily Stressed)Aggressive to same species/look-alikesTerritorial (Defends specific area)
Stocking calculator

Can your tank handle Black Phantom Tetra and Scarlet Badis?

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.

Black Phantom Tetra
Scarlet Badis
Test both in my tank

Behaviour & Temperament

Black Phantom Tetra is a peaceful species (2/10), while Scarlet Badis is generally mild-mannered (3/10). This modest difference means Scarlet Badis may occasionally assert dominance over Black Phantom Tetra.

Black Phantom Tetra and Scarlet Badis both frequent the Middle (Open Water) 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: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Shrimp eaters may also prey on very small nano fish.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Black Phantom Tetra and Scarlet Badis to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations. A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

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 4–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Black Phantom Tetra and Scarlet Badis together, plan for an aquarium of at least 60 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.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Plants - Densely covered, Plants - Floating, Leaf Litter/Blackwater, Plants - lighly covered, Sand (Sifters). 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 Needs Extra Planning in Practice

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Black Phantom Tetra and Scarlet Badis need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Black Phantom Tetra and Scarlet Badis.

Show 19 more tank sizes

Diet & Feeding

Feeding time deserves special attention with this pairing. Scarlet Badis is a known shrimp eater and may prey on small invertebrates or nano fish like Black Phantom Tetra.

Frequently Asked Questions

Can Black Phantom Tetra and Scarlet Badis live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 60 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Black Phantom Tetra and Scarlet Badis need?

A minimum of 60 litres (tank length at least 60 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 Black Phantom Tetra and Scarlet Badis 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 Black Phantom Tetra or Scarlet Badis aggressive?

Black Phantom Tetra is peaceful (2/10) and Scarlet Badis is generally mild-mannered (3/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Black Phantom Tetra and Scarlet Badis 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 Scarlet Badis's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Scarlet Badis 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 1, 2026
Last updated
May 1, 2026
Issues or corrections?
Contact the editorial team

Related Comparisons