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Black Harlequin Rasbora
Please Note: Due to variations within species, your item may not look identical to the image provided. Approximate size range may also vary between individual specimen.
Black Harlequin Rasbora (Trigonostigma heteromorpha)
Additional locales and sizes may be available!

Quick Stats

Care Level Easy
Temperament Peaceful
Color Form Tan
Diet Omnivore
Water Conditions 72-77° F, KH 6-10, pH 6.0-6.5
Max. Size 2"
Origin Asia
Family Cyrpinidae
Minimum Tank Size 10 gallons
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The Black Harlequin Rasbora is a popular aquarium fish. These fish have a black, triangle-shaped patch starting near the dorsal fin, and a mostly purple to black body. The male's patch is slightly rounded at the bottom with an extended tip, while the female's is straight. Females are larger than males.

Harlequins require an established planted aquarium. They should be kept in schools of six or more and in an aquarium with other small, peaceful fish.

Rasbora heteromorpha like to spawn on the undersides of broad-leaved plants. A breeding tank with shallow, warm, acidic, soft water with broad-leaved plants should be set up. Pair a young female (9-12 months old) with a two-year old male and feed them live foods. After spawning, remove the parents and keep the aquarium dark until the eggs hatch (after about 24 hours). Feed the fry infusoria.

An omnivore, Black Harlequin Rasboras do well on a diet of prepared flake food, as well as freeze-dried bloodworms and tubifex.

Approximate Purchase Size: Small: 3/4" to 1-1/4"; Medium: 1-1/4" to 1-3/4"

Customer Testimonials

Grady B Natick , MA
This fish is a must buy for any small to medium aquarium. I bought 4 and they truly are some of my favorite fish. All can alive and well, about 2 inches, and ate right away. If you are unsure about these, get them now. They really are amazing!! Very active as well, great for beginners and people with experience as well!
Pati Epsimos Revere , MA
been a week and all 6 of these little guys are acclimated and healthy and happy. I love buying small young fish and watch them grow. My other harlequins are now 3 years old and these little guys swim with their larger counterparts and love playing in the plants and powerhead. These baby harlequins are fun to watch! I Love them!
1-2 of 2 testimonials

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