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Rasboras are small, peaceful schooling fish from Southeast Asia and one of the best choices for a calm planted aquarium. The harlequin rasbora is a hardy classic, while chili and dwarf spotted rasboras (Boraras) are among the smallest fish you can keep, at well under an inch (2-2.5 cm).
They are true schooling fish: keep at least 8 to 10 of one species and they will swim together in the middle of the tank, showing their best colors. Because they are small and gentle, they work well with dwarf shrimp, snails, otocinclus and other peaceful nano fish.
- Water: soft, slightly acidic water suits them best, around 73-79 °F (23-26 °C), although captive-bred harlequins adapt to most tap water.
- Tank size: Boraras can live in a well-planted 8-10 gallon (30-40 L) tank; harlequins and scissortails need more length.
- Diet: fine flakes, micro pellets and small frozen foods such as daphnia or baby brine shrimp.
Avoid boisterous tank mates: large barbs or cichlids will stress them and outcompete them for food. Plants, a dark background and gentle flow bring out their natural behavior.
Rasboras
| Species | Min. liters | Size | Temp. | Difficulty |
|---|---|---|---|---|
 Harlequin rasbora Trigonostigma heteromorpha | 16 gal (60 L) | 1.8 in (4.5 cm) | 72–81 °F (22–27 °C) | Easy |
 Chili rasbora Boraras brigittae | 8 gal (30 L) | 0.8 in (2 cm) | 72–82 °F (22–28 °C) | Moderate |
 Dwarf rasbora Boraras maculatus | 11 gal (40 L) | 1 in (2.5 cm) | 75–82 °F (24–28 °C) | Moderate |
 Hengel's rasbora Trigonostigma hengeli | 14 gal (54 L) | 1.2 in (3 cm) | 73–82 °F (23–28 °C) | Moderate |
 Lambchop rasbora Trigonostigma espei | 14 gal (54 L) | 1.4 in (3.5 cm) | 73–82 °F (23–28 °C) | Easy |
 Red-line rasbora Rasbora pauciperforata | 26 gal (100 L) | 2.4 in (6 cm) | 73–82 °F (23–28 °C) | Moderate |
 Scissortail rasbora Rasbora trilineata | 40 gal (150 L) | 4.7 in (12 cm) | 72–79 °F (22–26 °C) | Easy |
No species match those filters.