Lambchop Rasbora (Trigonostigma espei) Warm-toned, peaceful and beautifully streamlined, the Lambchop Rasbora is a striking Southeast Asian schooling fish with glowing orange-copper colour and a distinctive black “lambchop” marking along the rear half of the body. Smaller and more slender than the classic Harlequin Rasbora, Trigonostigma espei is an excellent choice for planted community aquariums and larger nano-style displays. Quick Facts Scientific name: Trigonostigma espei Common names: Lambchop Rasbora, Espei Rasbora Origin: Southeast Asia Adult size: Approximately 3–4 cm Tank size: 40L+ recommended Difficulty: 🟢 Easy Temperament: Peaceful and social Swimming level: Mid to upper water Best kept: Groups of at least 6, with 10+ strongly preferred Is this for you? ✔️ Perfect if: You want a smaller alternative to Harlequin Rasboras. You like orange and copper-toned schooling fish. You have a planted aquarium. You want a peaceful community species. You enjoy fish that look far better in larger groups. ❌ Avoid if: You intend to keep only one or two individuals. You keep large predatory fish. Your aquarium has no open swimming space. You want a solitary centrepiece fish rather than a social species. Why choose Lambchop Rasboras? The Lambchop Rasbora is one of the most attractive smaller Trigonostigma species. Its body develops warm orange, copper and reddish tones, particularly when mature and settled, while the distinctive black marking along the rear half of the body creates the characteristic lambchop-shaped profile. Compared with the Harlequin Rasbora, T. espei is generally slimmer, smaller and more intensely orange, making it especially well suited to planted tanks where a group can move naturally through midwater. Their peaceful nature and manageable size also make them extremely easy to integrate with other small community species. Benefits Beautiful orange-copper colouration Distinctive black lambchop marking Smaller than Harlequin Rasboras Peaceful community temperament Excellent schooling behaviour Ideal for planted aquariums Easy to feed Suitable for beginner and experienced aquarists Care made simple Temperature: Approximately 23–28°C pH: Approximately 5.5–7.5 Water: Clean and stable; soft to moderately mineralised water is suitable Diet: Quality micro pellets and flakes supplemented with live or frozen foods Excellent foods: Brine shrimp, daphnia and other appropriately sized foods Flow: Gentle to moderate Setup: Plants around the sides and rear with open swimming space through the centre Darker substrate and floating plants can help enhance colour. Keep in a proper group rather than individually. Use a secure lid. Lambchop vs Harlequin Rasbora These two species are closely related and regularly confused in the aquarium trade. Lambchop Rasbora – Trigonostigma espei Generally smaller and slimmer with stronger orange colour and a narrower black marking shaped like a lambchop or hockey stick. Harlequin Rasbora – Trigonostigma heteromorpha Generally deeper-bodied with a much broader triangular black marking extending across the rear half of the body. Both are excellent community fish, but they are separate species and should be identified correctly. Pairs perfectly with Ember Tetras Small peaceful Gouramis Corydoras Otocinclus Kuhli Loaches Peaceful dwarf cichlids NTA Insight: If you like Harlequin Rasboras but want something slightly smaller, slimmer and more orange, Trigonostigma espei is a fantastic alternative. Don't stop at six if the aquarium has room. A larger group of 10–15 fish produces a much stronger display and generally gives you more confident behaviour and better colour. FAQ Is Rasbora espei still the correct scientific name? The species is commonly referred to in the hobby as Rasbora espei, but the accepted scientific name is Trigonostigma espei. How large do Lambchop Rasboras grow? Adults generally reach approximately 3–4 cm, making them smaller than the classic Harlequin Rasbora. How many should I keep? Keep at least six, although groups of ten or more are strongly preferred where aquarium space allows. Are Lambchop Rasboras schooling fish? Yes. They are social fish and should be maintained as a group. Relaxed fish may form a loose school rather than swimming tightly together at all times. Are Lambchop Rasboras peaceful? Yes. They are very peaceful community fish and mix well with similarly sized non-aggressive species. What is the difference between Lambchop and Harlequin Rasboras? Lambchop Rasboras are generally smaller and slimmer with a narrower black marking and stronger orange colouration. Harlequin Rasboras are deeper-bodied with a broader triangular black marking. What should I feed them? Offer quality micro pellets or flakes as a staple and supplement these with small live or frozen foods such as brine shrimp and daphnia. Can Lambchop Rasboras live with shrimp? Adult dwarf shrimp can often coexist with them, but newborn shrimplets may be eaten opportunistically. Dense moss and plant cover will improve shrimplet survival. Can they live with Bettas? Potentially, depending on the temperament of the individual Betta. Provide sufficient space, plants and visual cover and monitor the fish carefully. Can Lambchop Rasboras breed in aquariums? Yes. Like other Trigonostigma, they typically place eggs on or beneath suitable plant leaves. Adults provide no parental care and may eat eggs, so intentional breeding is best attempted in a separate setup. How can I tell males and females apart? Mature females generally become fuller-bodied when carrying eggs, while males remain slimmer and may show stronger colour. Sexing juveniles can be difficult. Are they suitable for beginners? Yes. Lambchop Rasboras are hardy, peaceful and straightforward to feed once the aquarium is properly cycled and stable. How long do Lambchop Rasboras live? With clean stable water, a varied diet and suitable social conditions, they generally live for approximately 4–6 years. Rasbora espei is a small, colorful freshwater fish native to Southeast Asia. It is a member of the Cyprinidae family, which also includes carps and minnows. Its scientific name is Rasbora espei. It is a very active fish and is often found in groups in the wild. It has a bright yellowish-green body with dark stripes and spots covering its sides, tail, and fins. It has been known to reach a maximum size of up to four inches in length. The Rasbora espei is an omnivore that feeds on both plant and animal matter. It is a peaceful fish that is often kept in community aquariums with similarly sized, non-aggressive fish. It has a lifespan of up to five years with proper care.
