If you buy through our links, Amazon pays us a small commission at no extra cost to you. That’s how we keep the site running. How we choose.
Contents
Overview
The lambchop rasbora (Trigonostigma espei) is the petite cousin of the harlequin rasbora. It lives in streams and flooded areas of southeastern Thailand and Cambodia, and it stands out for its rich coppery orange color and a slimmer black marking than the harlequin's, shaped, as the name suggests, like a lamb chop.
At around 1.5 inches (3.5 cm), it fits beautifully in small and medium planted tanks, where tight schools put on a warm glow under soft lighting. It's just as peaceful as its relative and nearly as hardy, though it does appreciate soft water and warmer temperatures to show its best orange.
Care and tank setup
A school of ten or more does well in a tank 24 inches long, around 15 gallons (54 liters), with plenty of plants and an open swimming area.
- Water: soft to moderately hard and slightly acidic; keep it very stable with regular partial changes. Color improves noticeably in soft water.
- Temperature: they like the warm end of the range, so don't pair them with cool-water fish.
- Decor: broad-leaved plants, moss, floaters to diffuse the light and a dark substrate. Indian almond leaves and driftwood add tannins they appreciate.
- Tank mates: chili and other micro rasboras, small tetras, pygmy corydoras, otocinclus, dwarf gouramis, bettas and dwarf shrimp.
A common mistake is keeping just four or five alongside bigger fish; they turn skittish and pale. In a large school with calm companions they stay out in the open all day.
Feeding
A small-mouthed omnivore. Offer fine flakes, micro pellets and small live or frozen foods such as baby brine shrimp, daphnia or cyclops. Several small feedings a day keep their color and condition up, and live baby brine shrimp is a great way to condition them before breeding.
Breeding
They spawn just like harlequins: the pair flips upside down under a broad leaf (crypts, anubias) and attaches the eggs to it. Success is more likely in very soft, acidic water in a separate tank with a well-fed pair. Remove the adults afterward and feed the fry infusoria for the first few days.
Compatible tank mates
Species from our database that share water parameters, size and temperament with the Lambchop rasbora. Calculated from the data in each profile.
Bristlenose pleco Ancistrus sp. 26 gal (100 L) · 72–81 °F (22–27 °C) 
Betta fish Betta splendens 7 gal (25 L) · 75–82 °F (24–28 °C) 
Bronze cory Corydoras aeneus 21 gal (80 L) · 72–81 °F (22–27 °C) 
Zebra danio Danio rerio 16 gal (60 L) · 64–77 °F (18–25 °C) 
Guppy Poecilia reticulata 14 gal (54 L) · 72–82 °F (22–28 °C) 
Cherry barb Puntius titteya 16 gal (60 L) · 73–81 °F (23–27 °C) 
Tiger barb Puntigrus tetrazona 26 gal (100 L) · 72–79 °F (22–26 °C) 
Nerite snail Neritina natalensis 5 gal (20 L) · 72–82 °F (22–28 °C) 
Horned nerite snail Clithon corona 5 gal (20 L) · 72–82 °F (22–28 °C) 
Panda cory Corydoras panda 16 gal (60 L) · 68–77 °F (20–25 °C) 
Amano shrimp Caridina multidentata 11 gal (40 L) · 64–82 °F (18–28 °C) 
Cherry shrimp Neocaridina davidi 5 gal (20 L) · 64–81 °F (18–27 °C) Check the compatibility of your whole tank →
What not to keep it with
Popular species you shouldn’t house with the Lambchop rasbora, and why.
- Common goldfish: incompatible temperatures, one may eat the other due to size
- Discus: incompatible temperatures, one may eat the other due to size
- Angelfish: one may eat the other due to size
- Clown loach: one may eat the other due to size
- Oranda goldfish: incompatible temperatures, one may eat the other due to size
- Oscar: one may eat the other due to size, incompatible temperaments
Recommended equipment
What you need to keep the Lambchop rasbora healthy, checked against Amazon stock.
Frequently asked questions
How many liters does a Lambchop rasbora need?
At least about 54 liters for a group of at least 10 fish. More space always helps keep the water stable.
What water temperature does the Lambchop rasbora need?
Between 23 and 28 °C, with a pH of 5.5 to 7.5.
What fish can live with the Lambchop rasbora?
Based on water, size and temperament, it fits with species such as Bristlenose pleco, Betta fish, Bronze cory, Zebra danio and Guppy. Use our compatibility calculator to check your whole tank.
Can the Lambchop rasbora be kept with shrimp?
Yes: it usually won’t eat adult shrimp, though some shrimplets may get picked off. A tank with plenty of moss gives the babies cover.
