Lambchop Rasbora

Trigonostigma espei

Also sold as False harlequin rasbora · Espei · Lamb chop rasbora

Synonyms Espei rasbora · Lamb chop · Rasbora espei

Lambchop Rasbora (Trigonostigma espei) is a peaceful freshwater fish that reaches about 3 cm (1.2 in) and swims in open water in a shoal. It wants 73–82°F (23–28°C) and pH 5.5–7.5, is kept in groups of 8 or more, and needs a tank of at least 40 L (11 gal).

Lambchop Rasbora (Trigonostigma espei)

At a glance

TypeFish
Adult size3 cm (1.2 in)
Minimum tank40 L (11 gal)
Group size8 or more
Temperature73–82°F (23–28°C)
pH5.5–7.5
TemperamentPeaceful
GH1–10
Lifespan2–5 years

Before it goes in

  • Lambchop Rasbora needs at least 40 L (11 gal). The smallest size in this library that clears that is the 15 Gallon.
  • Keep 8 or more. Below that it hides, colours down and is far more likely to be picked on.
  • It is the wrong size to share a tank with Goldfish, Angelfish and Axolotl: it ends up as food.
  • It holds at 73–82°F (23–28°C). That shares a window with Betta and Cherry Shrimp.
  • A group of 8 takes up roughly 44% 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 40 L (11 gal). The smallest size here that clears it is the 15 Gallon.

How many should I keep?

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

What water does it want?

73–82°F (23–28°C), pH 5.5–7.5, GH 1–10.

How long does it live?

2–5 years in a tank that suits it. That is how long you are signing up for.

Good tank mates

Often compared with

Lambchop RasboraHarlequin RasboraDwarf Spotted Rasbora
Adult size3 cm4.5 cm2.5 cm
Min tank40 L40 L41 L
Group8+6+8+
Temperature73–82°F (23–28°C)72–81°F (22–27°C)68–82°F (20–28°C)

More livestock

Plan a tank with Lambchop Rasbora →

Sources (3) · checked Sep 2026