The Blackline Rasbora,  Rasbora borapetensis, is an aquarium fish of the family Cyprinidae found in Asia from the Mekong, Chao Phraya and Mae Klong basins, and also northern Malay Peninsula. It grows to about 4  to 6,5 cm.

It is a lively, peaceful schooling fish that should be kept together with other peaceful fishes in the community aquarium. The aquarium should be planted heavily on the sides and background. Leave a lot of free swimming space in the middle. On the surface use a few floating plants to dim the light at some places in the aquarium. Changing of the water regularly is important.

The Rasbora borapetensis has an incomplete lateral line, reaching at most to the anal fin origin - a dark brown mid-lateral stripe from the gill opening to somewhat in front of the caudal fin base, not widening posteriorly and above it is a second, pale stripe. There is no black pigment on the fins.

The Blackline Rasbora occurs in ponds, streams and drains, usually in slow flowing, often somewhat turbid water, from midwater level to the surface in nearly all ponds, ditches, canals and reservoir margins of 2 meters depth or less. It prefers temperatures between 22 and 26° C. It feeds on zooplankton, insects, worms, Tubifex, water fleas, mosquito larvae, dried food and crustaceans. You should give them small live food. Dry food is accepted as well.

Mistakenly called the "Brilliant Rasbora" on occasion, mostly by marketers, it should not be confused with the Rasbora Einthoueni,  which properly is called the Brilliant Rasbora.

Breeding is not easy. Transfer the parents to another aquarium with a lower water level. After a few days 30-40 eggs are laid and fertilized. Immediately after spawning the parents should be removed because they eat their own eggs. The eggs hatch after 36 hours. When the young are swimming free feed them Artemia-nauplii. Temperature: 25 ° C (80 ° F). Lays adhesive eggs.

The Rasbora borapetensis is a lively swimmer, although it tends to congregate in peaceful shoals. It likes scattered vegetation, but needs plenty of open water for swimming.

Females are beautifully marked and are stouter than males.

Symbols
Legend:

Maximum
Temperature:

79°F

Minimum
Temperature:

72°F

pH
Range:

6.5 - 7

GH
Range:

5 - 8

Swimming
Level:

Water
Movement:

Community tank.
Generally peaceful.

Predator.
Generally aggressive.

Moderate to
bright light. 

Low
Light.

Moderate to heavily planted tank.

Rock, or
bogwood.

Open sand or gravel. 

Active or
surface swimmer.

Likes hideaways and cover.

Live foods,
only.

Live or
prepared foods.