Harlequin Rasbora (Trigonostigma heteromorpha)
Harlequin Rasbora is a well-known species within the fishkeeping community. Often found in aquarium shops, this shimmering reddish-copper fish is also commonly referred to as Red Rasbora due to its distinctive body color.
These fish grow to a mature size of up to 2 inches. Though small, they are highly attractive with a metallic sheen and a dark black stripe extending from the rear half of the body to the tail. When kept in groups, they display fascinating interactive behaviors that enhance the visual appeal of the aquarium.
Harlequin Rasbora is an easy-to-care-for species suitable for community tanks.
| Feature | Detail |
|---|---|
| Scientific Name | Trigonostigma heteromorpha |
| Mature Size | Up to 2 inches |
| Color Pattern | Reddish-copper body with dark black stripe from rear to tail |
| Group Behavior | Displays active and colorful interactions in groups |
| Difficulty Level | Easy to care for |
FAQ
What is the typical size of a Harlequin Rasbora?
Harlequin Rasbora grow to a mature size of up to 2 inches.
What makes Harlequin Rasbora stand out in an aquarium?
Their metallic reddish-copper body color and a distinct dark black stripe running from the rear half to the tail make them visually striking. They also create dynamic interactions when kept in groups.
Is Harlequin Rasbora suitable for beginners?
Yes, Harlequin Rasbora is considered an easy-to-care-for species and is ideal for beginners looking to add a colorful, active fish to their community tank.

Frank Peake –
I bought a group of Harlequin Rasbora for my 10-gallon tank. They’ve been active and colorful since day one. The black stripe on their bodies really stands out. They don’t need much space or special care, which makes them perfect for a new fishkeeper like me.
Blake Oliver –
These fish are a joy to watch. When they move together, the shimmering effect is beautiful. I kept them in a community tank with tetras and they get along well. Easy to maintain and very affordable.
Piers Robertson –
The color is vibrant and the fish are active. I noticed they prefer slightly cooler water temperatures. Still, they’re a great addition to a small community tank and don’t cause any issues.