Tankwise

A large, shimmering African tetra whose males trail rainbow-tinged fins — a stunning shoaler.

  • Temperature23–27 °C
  • pH6–7.5
  • Minimum tank90 L
  • DifficultyIntermediate
FoodFlake/pellet + frozen
Feeding1–2 feeds a day
Water change25% weekly

Behaviour and habits

The Congo tetra is a large, shimmering African tetra whose males trail rainbow-tinged, veil-like fins, and it is one of the most graceful freshwater fish. It is an active, peaceful shoaler that needs length to swim and a group to show its colours, and it looks best in subdued light against a dark, planted background. It is a mid-water swimmer, gliding rather than darting, and it becomes far more spectacular as it matures in a settled, roomy tank.

What to feed, and how often

Flake or pellet plus frozen bloodworm, daphnia and the odd vegetable; feed once or twice a day. A varied diet keeps the males' fin colour and the body's iridescence strong, and it is an unfussy but fairly hearty eater.

Water changes and maintenance

Change about 25% weekly in soft-to-neutral water, matched closely. It appreciates a bigger tank and a mature, stable setup more than the small tetras do, and it dislikes sudden swings.

Care and how easy it is

Needs more space than the small tetras and settles best in a mature tank with a group of six or more; not for a cramped nano setup.

Common health problems

Prone to ich when stressed or moved; robust otherwise.

If it gets sick

Quarantine new fish, then keep the water warm and stable, and treat ich early.

Good tank mates

GuppyBeginner with population planning
GuppyPoecilia reticulata
  • 22-26 C
  • pH 7.0-8.5
  • 60 L+; 60 x 30 cm base
Livebearers | Social; males pursue females | Omnivore
PlatyBeginner
PlatyXiphophorus maculatus
  • 20–26°C
  • pH 7–8.2
  • 50 L+
Livebearers · Peaceful · Omnivore
MollyBeginner
MollyPoecilia sphenops
  • 22–28°C
  • pH 7–8.5
  • 70 L+
Livebearers · Peaceful · Omnivore

Best avoided with

Similar species

GuppyBeginner with population planning
GuppyPoecilia reticulata
  • 22-26 C
  • pH 7.0-8.5
  • 60 L+; 60 x 30 cm base
Livebearers | Social; males pursue females | Omnivore
PlatyBeginner
PlatyXiphophorus maculatus
  • 20–26°C
  • pH 7–8.2
  • 50 L+
Livebearers · Peaceful · Omnivore
MollyBeginner
MollyPoecilia sphenops
  • 22–28°C
  • pH 7–8.5
  • 70 L+
Livebearers · Peaceful · Omnivore

Compare at a glance

ParametersCongo tetraGuppyPlatyMolly
Parameters
Temp23–27 °C22–28 °C20–26 °C22–28 °C
pH6–7.56.8–87–8.27–8.5
GH4–15 °dGH8–20 °dGH10–25 °dGH12–25 °dGH
Min. tank90 L40 L50 L70 L
Size8 cm5 cm6 cm8 cm
DietOmnivoreOmnivoreOmnivoreOmnivore
TemperamentPeacefulPeacefulPeacefulPeaceful
DifficultyIntermediateBeginnerBeginnerBeginner

Care guides

GuideHow Often Should You Feed Fish?Overfeeding causes more aquarium problems than underfeeding. Here is a realistic feeding routine, and the signs that you are giving too much.GuideHow Often Should You Change Aquarium Water?Water changes remove waste that the filter cannot, and keep minerals topped up. There is no single number, but there is a simple way to find yours.GuideHow to Treat Ich (White Spot Disease)Ich looks alarming but is one of the most treatable fish diseases. Act early, raise the heat, and it clears within a week or two — here is how.GuideFishless Cycling: The Kindest Way to Start a TankFishless cycling builds the filter's bacteria before any fish goes in, so your first fish never lives through toxic water. Here is how to do it.GuideHow to Acclimate New Fish (Float and Drip)How you introduce a new fish decides whether it settles or stresses. Float, mix and net — the right way to acclimate a new arrival in half an hour.

New to the words? See the aquarium glossary.

Sources and research notes

Parameters are typical ranges for the species in home aquariums and vary with the individual fish and the water you use.