Siamese Dwarf Rasbora
Trigonostigma somphongsi
- Care level
- Intermediate
- Adult size
- 3 cm
- Minimum tank
- 54 litres
- Temperature
- 22–26 °C
Species profile
Scissortail Rasbora
Rasbora trilineata
Common names: Scissortail Rasbora, Three-Lined Rasbora
Recognized speciesRasboras
Adult size
Up to 15 cm
Typical adult length 10–15 cm.
Up to 15 cm
Countries of origin
Good fit for your tank?
Good fit for
- A large, long community aquarium
- A keeper who wants an active upper-level shoal
- A robust community with medium-sized fish
Think carefully if
- You have bought it as a small fish for a small tank
- The aquarium has no lid
- You keep very small fish or shrimp
A silver Southeast Asian rasbora that grows much larger than its shop size. Named for its flicking tail, it is hardy and active, and it needs a long aquarium with a lid.
Appearance and Identification
A long, silvery, torpedo-shaped body with a thin dark line along the flank and a deeply forked tail marked with black and white bars.
The black and white markings on the deeply forked tail, which flicks as the fish swims, are the best features to look for.
Mature females are rounder-bellied and often slightly larger than males.
Tank Requirements
- Suggested filter
- About 960–1,200 litres an hour
- Suggested heater
- About 250–350 W for this tank
- Minimum tank volume
- 240 litres
- Minimum tank length
- 120 cm
- Minimum group size
- 6
- Recommended group size
- 8
- Activity level
- Very active
- Flow preference
- Moderate
- Planting preference
- Moderately planted
- Lid recommended
- Yes
- Jumping risk
- High
Provide a long open swimming lane with plants or wood around the edges. Use a tight lid, as this fish jumps when startled.
Behaviour and Tankmates
An active, gregarious fish that uses the middle and upper water and shows better colour among its own kind.
Keep at least 6, and preferably more.
Not territorial.
Good with medium-sized peaceful fish, barbs, larger tetras, and loaches. Small tetras, small rasboras, and shrimp may become prey once this fish is adult.
Water Parameters
Acceptable pH depends on where the fish come from, with 6.5 to 7.5 usually ideal. Keep the water clean and well oxygenated.
Parameter caveat
Plan for the adult size, not the size in the shop. Acclimate slowly.
Feeding
- Diet types
- Insectivore, Omnivore
- Feeding frequency
- Once or twice daily
- Preferred foods
- Quality flake or small granulesUse as the daily staple, choosing a size every fish in the group can manage.
- Frozen bloodworm, daphnia, or brine shrimpRotate these a few times a week to improve condition and colour.
- Spirulina or vegetable flakeAdds plant matter that a meat-heavy diet lacks.
An omnivore that takes insects from the surface and readily accepts prepared foods.
Floating and slowly sinking foods suit its upper-level feeding.
Breeding
- Breeding type
- Egg Scatterer
- Breeding difficulty
- Easy
- Brood or egg count
- Often several hundred eggs
- Incubation
- 1 days
- Parental care
- None
- Baby foods
- Infusoria or parameciumNeeded for the first days after fry become free-swimming, because the fry are very small.
- Fine powdered fry foodUse sparingly as a supplement, and siphon out anything left uneaten.
- Newly hatched brine shrimpIntroduce once the fry are large enough to swallow it, usually after several days.
- MicrowormsA useful next step for fry that are still too small for brine shrimp.
An egg-scattering continuous spawner with no parental care, and comparatively easy to breed. For more fry, use a separate, dimly lit container with a mesh base to protect eggs from adults. Eggs hatch in about 18 to 48 hours.
Habitat and Origin
- Geographic origin
- Borneo, Cambodia, Indonesia, Laos, Malaya, Malaysia, Southeast Asia, Sumatra, Thailand
- Natural habitat
- Freshwater River, Lake, Slow River
- Aquarium contexts
- Breeding Aquarium, Large Aquarium
- Audience level
- Intermediate
Classification
- Profile type
- Recognized species
- Genus
- Rasbora
- Family
- Danionidae
- Species group
- Fish, Rasboras
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Sidestripe Rasbora
Rasbora paviana
- Care level
- Intermediate
- Adult size
- 9 cm
- Minimum tank
- 108 litres
- Temperature
- 22–26 °C
Strawberry Rasbora
Boraras naevus
- Care level
- Intermediate
- Adult size
- 2 cm
- Minimum tank
- 40 litres
- Temperature
- 20–28 °C
Three Spotted Dwarf Rasbora
Boraras micros
- Care level
- Intermediate
- Adult size
- 1.3 cm
- Minimum tank
- 40 litres
- Temperature
- 20–28 °C