Green Fire Tetra

Aphyocharax rathbuni

Also sold as Rathbun's bloodfin tetra

Green Fire Tetra (Aphyocharax rathbuni) is a semi-aggressive freshwater fish that reaches about 4.5 cm (1.8 in) and swims in open water in a shoal. It wants 68–79°F (20–26°C) and pH 6.5–7.5, is kept in groups of 6 or more, and needs a tank of at least 54 L (14 gal).

At a glance

Type	Fish
Adult size	4.5 cm (1.8 in)
Minimum tank	54 L (14 gal)
Group size	6 or more
Temperature	68–79°F (20–26°C)
pH	6.5–7.5
Temperament	Semi-aggressive
Lifespan	3–5 years
Eats shrimp	Shrimplets only

Before it goes in

Green Fire Tetra needs at least 54 L (14 gal). The smallest size in this library that clears that is the 15 Gallon.
Keep 6 or more. Below that it hides, colours down and is far more likely to be picked on.
Adult shrimp are safe; shrimplets will be eaten, so a shrimp colony will not grow in the same tank.
It is the wrong size to share a tank with Goldfish, Angelfish and Axolotl: it ends up as food.
It holds at 68–79°F (20–26°C). That shares a window with Betta and Cherry Shrimp, but not with Discus.
It is semi-aggressive — plan the tank around it rather than adding it to a finished community.
It nips fins, so long-finned fish are a bad match.
A group of 6 takes up roughly 61% of what a 15 Gallon will comfortably hold, so plan the rest of the stock around it.

What tank size does it need?

At least 54 L (14 gal). The smallest size here that clears it is the 15 Gallon.

How many should I keep?

6 or more. Fewer than that and it spends its time hiding instead of out in the open.

Will it eat shrimp?

Adults are safe, shrimplets are not. You can keep shrimp with it; you just will not get a growing colony.

What water does it want?

68–79°F (20–26°C), pH 6.5–7.5.

How long does it live?

3–5 years in a tank that suits it. That is how long you are signing up for.

Good tank mates

Tank mates from this library that share its temperature window, are peaceful and eat neither it nor its young: Cherry Shrimp, Bristlenose Pleco, Celestial Pearl Danio, Molly and Otocinclus.
Plants that hold up with it: Hygrophila corymbosa 'Siamensis', Water Sprite, Anubias nana 'Petite' and Cryptocoryne wendtii.

Often compared with

	Green Fire Tetra	Black Phantom Tetra	Head and Tail Light Tetra
Adult size	4.5 cm	4.5 cm	4.5 cm
Min tank	54 L	60 L	68 L
Group	6+	6+	6+
Temperature	68–79°F (20–26°C)	72–82°F (22–28°C)	75–82°F (24–28°C)
Eats shrimp	Shrimplets only	Yes	Shrimplets only

More livestock

Plan a tank with Green Fire Tetra →

Sources (4) · checked Sep 2026