Max Size: 6cm

Black Line Rasbora (Rasbora borapetensis)

The Blackline Rasbora is a robust, hardy, peaceful fish which can be housed with other temperate species. These fish are relatively widespread and prefer slow-moving water and a heavily planted aquarium.

This species of Rasbora is a true schooling fish and can always be seen in a tight school, darting back and forth in the middle and upper regions of an aquarium.

The Blackline Rasbora is streamlined, silver in colour and sports a dark brown to black, mid-lateral stripe leading from the gill opening to the front of the caudal fin base. Above that line is a gold bar and the caudal fin is a bright red colour.


Black Line Rasbora
Black Line Rasbora
Black Line Rasbora
Quick Facts
Scientific NameRasbora borapetensis
Other NamesRed-tailed Rasbora, Bora Bora Rasbora, Brilliant Rasbora, Borapet Rasbora
OriginsCambodia, China, Laos, Malaysia, Thailand, Vietnam
Aquarium LevelMiddle - Top
DifficultyBeginner - Intermediate
Best kept asGroups 6+
Lifespan5 - 7 years
Water Parameters
Water TypeFreshwater
PH6.5 - 7.0
GH5 - 12
KH3 - 7
71 - 79℉
21.7 - 26.1℃


In the home aquarium, the Black Line Rasbora will readily accept most good quality dried foods such as granules, flakes and sinking pellets. These modern food products have been developed to provide all adequate nutrition to maintain your fish's health and dietary requirements.

Providing additional foodstuffs such as live, frozen, and freeze-dried meals such as bloodworm, daphnia, and tubifex once or twice a week will provide additional benefits to your fish's health and well-being but is not a must for this fish.

It should be noted that bloodworms should only be given as an occasional treat and should not be used as the staple diet as they are difficult for fish to digest and can potentially cause blockages.

This fish is an omnivore in the wild, meaning it will consume some vegetable matter. Although most modern fish foods take this into account and include them in their products, you can still supplement your fish's diet with blanched vegetables such as spinach, broccoli, and zucchini. Ensure you do not overfeed your fish and remove any leftovers the following day.

Sexual Dimorphism

It is quite tricky to differentiate males from females as they look very similar. However, the females are slightly fatter, broader, and deeper bodied, and have a whitish belly, whereas the males are more slender and smaller, with a creamy-yellow or reddish belly.

Other Rasboras of interest

Blue Line Rasbora(Rasbora sarawakensis)
Chilli Rasbora(Boraras Brigittae)
Clown Rasbora(Rasbora kalochroma)
Dwarf Rasbora(Boraras maculatus)
Emerald Eye Rasbora(Brevibora dorsiocellata)
Exclamation Point Rasbora(Boraras urophthalmoides)
View all Rasboras
Date Added: 01/10/2020 - Updated: 19/01/2022 14:11:43