Harlequin Rasbora Care and Breeding: Everything You Need to Know

I’m super excited to bring you a species profile of a fish we’ve had in the fish room for a while now: the Harlequin Rasbora. Harlequin Rasboras are excellent additions to any aquarium, known for their tight schooling behavior and vibrant coloration.

Although considered a beginner-friendly fish, the Harlequin Rasbora is a rewarding addition to any aquarium, even for experienced hobbyists. Hope you find this guide helpful.

Overview of the Harlequin Rasbora

I definitely want to take a closer look at the Harlequin Rasbora. This is a great fish that we have had in our fish room for a long time. Everything we’re going to say here pretty much applies to the Porkchop Rasbora as well. While they share many physical similarities, the Harlequin Rasbora is distinguished by its deeper pinkish coloration and slightly different body shape.

The Porkchop Rasbora has a slightly different pattern to that black part of their body, and they don’t get quite as pinkish, but both of them are great fish.

A 40-gallon breeder tank is ideal for Harlequin Rasboras, often paired with Congo Tetras and Angelfish. I love this fish because they tend to school tightly and stay relatively small.

Habitat and Behavior

In nature, you’ll find them throughout Malaysia, Thailand, and Singapore, usually in streams. The water is often on the softer, more acidic side. Size-wise, these fish stay relatively small at around an inch and a half or so. Females tend to be a little more round, but both the males and females show great color.

Another thing I like about them is that they’re peaceful. We’ve had groups of these fish in lots of different environments, and they pretty much just seem to stay to themselves. They’re not overly fin-nippy or anything like that.

Harlequin Rasboras are compatible with peaceful tank mates, such as Angelfish, and thrive in community setups. I really like that because of their schooling behavior and peaceful temperament.

Lifespan and Resilience

In terms of lifespan, we’ve had Harlequin Rasboras last at least five years in our fish room. Harlequin Rasboras are hardy, long-lived fish that adapt well to a range of water parameters, making them ideal for various setups.

Tank Mates and Setup

For tank mates, I’ve already shown you the Congo Tetras and the Angelfish. Here, you’re seeing some Neons and Siamese Algae Eaters in this tank as well. There are many compatible tank mates for Harlequin Rasboras, offering great flexibility in community aquariums.

Other types of rasboras would be a great choice too. Other great tank mate options include Green Kubotai Rasboras, Galaxy Rasboras, and Chili Rasboras.

Cory Cats and most types of Plecos also work really well. We keep ours with Bristlenose Plecos and Clown Plecos. Mystery Snails or Nerite Snails would be great tank mates too.

Water Parameters

Regarding temperature, we generally keep our fish tanks close to 80°F. These fish tolerate typical tropical fish temperatures, anywhere from 75°F to 82°F. For pH, they have a wide range of acceptable measurements. We keep our tanks at a pH of around 8, but they would probably be more comfortable at neutral or slightly acidic levels.

For water hardness, they do well anywhere from 2 to 15 degrees GH and KH. Our water is on the harder side, but they thrive. Just make sure your tank is cycled with no ammonia or nitrites.

Feeding and Diet

Feeding these fish is relatively easy. We feed all of our fish N Fin foods, including N Fin Community and Cichlid Flakes (crushed up for smaller fish). They love live baby brine shrimp and frozen brine shrimp. They’re not picky eaters.

Tank Size and Decoration

For tank size, give them at least a 10-gallon setup. Keep these fish in groups—a minimum of six is recommended, but larger groups (12–15 or more) will really bring out their schooling behavior.

Decorating the tank is flexible. Substrate doesn’t matter because these fish don’t interact with it, so base it on the needs of other fish in the tank. Gravel, sand—either is fine. Add live or fake plants, rockwork, and driftwood for structure.

Breeding Harlequin Rasboras

If you want to breed them, it’s not beginner-friendly. Harlequin Rasboras are egg scatterers. You’ll need a spawning mop and a separate tank for fry, as adults will eat the eggs and fry. Feeding the fry requires infusoria or specialized fry food due to their tiny size.

Key Information

Final Thoughts

Overall, the Harlequin Rasbora is a vibrant and peaceful fish that brings life and color to any aquarium. They school tightly, show fantastic color, and are peaceful. The only challenge is ensuring their tank mates aren’t overly large or aggressive. But when fully grown and showing their pinkish or orange hues, they truly stand out in any aquarium.