Red Rainbowfish

Glossolepis incisus

Also sold as Red Irian rainbow · Salmon red rainbowfish

Red Rainbowfish (Glossolepis incisus) is a peaceful freshwater fish that reaches about 15 cm (5.9 in) and swims in open water in a shoal. It wants 72–77°F (22–25°C) and pH 7–8, is kept in groups of 6 or more, and needs a tank of at least 108 L (29 gal).

At a glance

Type	Fish
Adult size	15 cm (5.9 in)
Minimum tank	108 L (29 gal)
Group size	6 or more
Temperature	72–77°F (22–25°C)
pH	7–8
Temperament	Peaceful
Lifespan	5–8 years
Eats shrimp	Yes

Before it goes in

Red Rainbowfish needs at least 108 L (29 gal). The smallest size in this library that clears that is the 29 Gallon.
Keep 6 or more. Below that it hides, colours down and is far more likely to be picked on.
It eats shrimp. Cherry Shrimp, Crystal Red Shrimp and Bamboo Shrimp are on the menu.
It is the wrong size to share a tank with Iridescent Shark, Senegal Bichir and Black Ghost Knifefish: it ends up as food.
It holds at 72–77°F (22–25°C). That shares a window with Betta and Cherry Shrimp, but not with German Blue Ram and Discus.
A group of 6 takes up roughly 184% of what a 29 Gallon will comfortably hold, so plan the rest of the stock around it.

What tank size does it need?

At least 108 L (29 gal). The smallest size here that clears it is the 29 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?

Yes. Shrimp are food to it, so pick one or the other.

What water does it want?

72–77°F (22–25°C), pH 7–8.

How long does it live?

5–8 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: Goldfish, 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

	Red Rainbowfish	Red Tail Shark	Boesemani Rainbowfish
Adult size	15 cm	12.5 cm	12 cm
Min tank	108 L	243 L	200 L
Group	6+	1+	6+
Temperature	72–77°F (22–25°C)	68–79°F (20–26°C)	75–82°F (24–28°C)
Eats shrimp	Yes	Yes	Yes

More livestock

Plan a tank with Red Rainbowfish →

Sources (5) · checked Sep 2026