Lambchop rasbora
Trigonostigma espei
easy careOverview
The lambchop rasbora (Trigonostigma espei) is the slimmer, more intensely coloured cousin of the harlequin. A warm copper-orange body carries a distinctive black hook — the “lambchop” mark — and a tight shoal drifting through a planted tank is one of the prettier sights in the nano hobby. It is peaceful, hardy and easy, making it an ideal shoaling fish for a beginner community.
Tank & water
A shoal of six is comfortable in 40 litres (10 gallons), with more space allowing a fuller, more natural group. Lambchops occupy the middle water and appreciate open swimming room framed by plants.
- Temperature: 23–28 °C, held with a steady heater.
- Water: soft to neutral, pH 6.0–7.0, suits them best, though they adapt to slightly harder water if it is stable.
- Filtration: a gentle filter keeps things clean without a strong current.
- Planted: dark substrate and background plants intensify their colour.
Feeding
Lambchops are undemanding omnivores. A quality micro-pellet or flake forms the staple, sized down for their small mouths, with frequent treats of frozen or live daphnia, cyclops, baby brine shrimp and finely chopped bloodworm. A varied diet keeps their copper colour rich and their finnage in good condition. Feed small amounts once or twice daily, only what the shoal clears quickly, to protect water quality in a smaller tank.
Tankmates
Peaceful and non-nippy, lambchops mix happily with other calm nano fish: harlequin and kubotai rasboras, celestial pearl danios, small tetras, pygmy corydoras, dwarf gouramis, snails and dwarf shrimp. Avoid large or aggressive tankmates.
With a full shoal in a mature, planted tank, the lambchop rasbora is a colourful, low-maintenance choice — see our beginner tank and nano aquarium picks to build around it.
Lambchop rasbora — frequently asked questions
What is the difference between a lambchop and a harlequin rasbora?
They are close cousins. The lambchop (Trigonostigma espei) is smaller and more slender, with a warmer copper-orange body and a narrower, hook-shaped black mark, while the harlequin is deeper-bodied with a broad triangular patch. Care is essentially the same.
How many lambchop rasboras should I keep together?
Six is the minimum and eight to twelve is better. They are a shoaling species that colours up and behaves naturally only in a group, so always buy several at once.
Are lambchop rasboras good in a planted tank?
Excellent. Their copper-orange colour pops against green plants and dark substrate, and a dense planted layout gives them the security that brings out their best behaviour and shoaling.
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