Can Freshwater Angelfish and Threadfin Rainbowfish Live Together?

🔴Not Recommended

Freshwater Angelfish and Threadfin Rainbowfish 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

Freshwater Angelfish

Pterophyllum scalare

Threadfin Rainbowfish

Iriatherina werneri

🐠Family Group
Freshwater Angelfish
Cichlids - South American
Threadfin Rainbowfish
Rainbowfish
Temperament
Freshwater Angelfish
Semi-Aggressive (6/10)
Threadfin Rainbowfish
Peaceful (1/10)
Temperature
✓ Compatible
Freshwater Angelfish
24–30°C
Threadfin Rainbowfish
23–29°C
pH Range
✓ Compatible
Freshwater Angelfish
6–7.8
Threadfin Rainbowfish
5.5–7.5
Hardness (dGH)
✓ Compatible
Freshwater Angelfish
3–15
Threadfin Rainbowfish
1–12
Water Type
✓ Compatible
Freshwater Angelfish
Freshwater Only
Threadfin Rainbowfish
Freshwater Only
Flow Preference
✓ Compatible
Freshwater Angelfish
Low
Threadfin Rainbowfish
Low
Min Tank Volume
Combined: 180 L
Freshwater Angelfish
150 L
Threadfin Rainbowfish
60 L
Swimming Level
Shared: 2 zones
Freshwater Angelfish
MiddleTop
Threadfin Rainbowfish
TopMiddle
🏷️Behavior Tags
Freshwater Angelfish
Piscivore (Eats small/nano fish)Shrimp EaterAggressive to same species/look-alikesTerritorial (Defends specific area)Fin Nipper
Threadfin Rainbowfish
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)Jumper (Lid Required)Hyperactive / Fast SwimmerAggressive Eater (Starves shy fish)

Behaviour & Temperament

Freshwater Angelfish is a moderately assertive species (6/10), while Threadfin Rainbowfish is peaceful (1/10). This notable difference means Freshwater Angelfish may occasionally assert dominance over Threadfin Rainbowfish.

Freshwater Angelfish and Threadfin Rainbowfish both frequent the Middle (Open Water) and Top (Surface) 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 Piscivore (Eats small/nano fish) behaviour of one fish directly conflicts with the Nano / Bite-sized (Predation Risk) trait of the other — piscivorous fish will prey on nano-sized tank mates..

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

Worth noting: Threadfin Rainbowfish is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 24°C and 29°C. Aim for the midpoint of this range (around 26.5°C) for optimal comfort.

Both fish can tolerate a pH between 6 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 3–12 dGH. Regular testing will ensure conditions stay within this range. An aquarium test kit is recommended for monitoring.

Tank Setup

To house Freshwater Angelfish and Threadfin Rainbowfish together, plan for an aquarium of at least 180 litres with a minimum length of 90 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, Driftwood (Digestion/Hiding), Plants - lighly covered, Plants - Floating. 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.

Find the right tank equipment

Browse tanks, décor, and equipment suited for this setup.

Diet & Feeding

Feeding time deserves special attention with this pairing. Freshwater Angelfish is a known shrimp eater and may prey on small invertebrates or nano fish like Threadfin Rainbowfish.

Because Threadfin Rainbowfish is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Freshwater Angelfish receives an adequate share.

Frequently Asked Questions

Can Freshwater Angelfish and Threadfin Rainbowfish live together?

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

What size tank do Freshwater Angelfish and Threadfin Rainbowfish need?

A minimum of 180 litres (tank length at least 90 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 Freshwater Angelfish and Threadfin Rainbowfish together?

Keep the aquarium between 24°C and 29°C. A target of around 26.5°C sits comfortably within both species' preferred ranges.

Are Freshwater Angelfish or Threadfin Rainbowfish aggressive?

Freshwater Angelfish is moderately assertive (6/10) and Threadfin Rainbowfish is peaceful (1/10). The gap in aggression levels means the calmer fish may experience stress from the more assertive one.

What pH do Freshwater Angelfish and Threadfin Rainbowfish need?

Both species overlap in the 6–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Freshwater Angelfish nip Threadfin Rainbowfish's fins?

Freshwater Angelfish is a known fin nipper. If Threadfin Rainbowfish has long or flowing fins, there is a real risk of fin damage. Keeping Freshwater Angelfish in a larger group can help redirect nipping behaviour toward conspecifics.

How do I manage Freshwater Angelfish's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Freshwater Angelfish 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.


Related Comparisons

Freshwater Angelfish & Bolivian Ram

·

🟡Possible with Caution
Freshwater Angelfish: PeacefulBolivian Ram: Peaceful

Freshwater Angelfish & Discus

·

🟡Possible with Caution
Freshwater Angelfish: PeacefulDiscus: Peaceful

Freshwater Angelfish & German Blue Ram

·

🟡Possible with Caution
Freshwater Angelfish: PeacefulGerman Blue Ram: Peaceful

Freshwater Angelfish & Uaru

·

🟡Possible with Caution
Freshwater Angelfish: PeacefulUaru: Peaceful

Freshwater Angelfish & Agassiz's Dwarf Cichlid

·

🟡Possible with Caution
Freshwater Angelfish: PeacefulAgassiz's Dwarf Cichlid: Peaceful

Freshwater Angelfish & Cockatoo Dwarf Cichlid

·

🟡Possible with Caution
Freshwater Angelfish: PeacefulCockatoo Dwarf Cichlid: Peaceful

Threadfin Rainbowfish & Boeseman's Rainbowfish

·

🟡Possible with Caution
Threadfin Rainbowfish: PeacefulBoeseman's Rainbowfish: Peaceful

Threadfin Rainbowfish & Dwarf Neon Rainbowfish (Praecox)

·

🟡Possible with Caution
Threadfin Rainbowfish: PeacefulDwarf Neon Rainbowfish (Praecox): Peaceful

Threadfin Rainbowfish & Forktail Blue-eye

·

🟡Possible with Caution
Threadfin Rainbowfish: PeacefulForktail Blue-eye: Peaceful

Threadfin Rainbowfish & Gertrude's Spotted Blue-eye

·

🟡Possible with Caution
Threadfin Rainbowfish: PeacefulGertrude's Spotted Blue-eye: Peaceful

Threadfin Rainbowfish & Red Rainbowfish

·

🟡Possible with Caution
Threadfin Rainbowfish: PeacefulRed Rainbowfish: Peaceful

Threadfin Rainbowfish & Turquoise Rainbowfish

·

🟡Possible with Caution
Threadfin Rainbowfish: PeacefulTurquoise Rainbowfish: Peaceful