The harlequin rasbora is a vibrant little fish that will add a splash of color to any aquarium. These pint-sized powerhouses are like jewels in the water, shimmering and shining as they swim gracefully through their aquatic home. Their striking red and black patterns are sure to catch the eye of any fish enthusiast.
These fish are hardy, easy to care for, and make great additions to community tanks. They are also peaceful and non-aggressive, making them great tankmates for a variety of other fish species. Whether you’re a beginner or an experienced aquarist, the harlequin rasbora is an interesting fish to consider for your next livestock addition.
| Care Data | Description |
|---|---|
| Scientific Name | Trigonostigma heteromorpha |
| Tank Size | 5 gallons (19L) |
| Water Temperature | 72-82°F (22-28°C) |
| pH Range | 6.0-7.0 |
| Water Hardness | Soft to medium-hard |
| Lighting | Moderate lighting |
| Diet | Omnivorous, accepts variety of foods |
| Social Behavior | Schooling fish, kept in groups of at least 6 individuals |
| Compatibility | Peaceful and non-aggressive, suitable for community tanks |
| Maximum Size | 2 inches (5cm) |
| Lifespan | 3-5 years with proper care |
Appearance
The harlequin rasbora has a deep, laterally compressed body that is adorned with a striking red and black pattern. Their fins are transparent, adding to the overall ethereal appearance of the fish. These fish have three dark, triangular markings on their sides, giving them the appearance of a harlequin mask.
Lifespan
The harlequin rasbora has an average lifespan of around 3-5 years with proper care.
Average Size and Growth Rate
Adults can reach up to 2 inches (5cm) in length, but more commonly reach around 1.5 inches (3.8cm). They have a moderate growth rate and will reach their full size within the first year of their life.
Tank Size
A single harlequin rasbora can be kept in a tank as small as 5 gallons (19L), but for a small group, a tank of at least 10 gallons (38L) is recommended.
Water Parameters
The harlequin rasbora is a tropical fish, so the water temperature should be kept between 72-82°F (22-28°C) with a pH range of 6.0-7.0. They do well in a wide range of water hardness, from soft to medium-hard.
Diet
The harlequin rasbora is an omnivore and will accept a variety of foods including flakes, pellets, and frozen or live foods such as brine shrimp, daphnia, and bloodworms. It’s important to provide a varied diet to ensure optimal health and coloration.
| Food Option | Description |
|---|---|
| Brine Shrimp | Rich in protein and essential amino acids, promoting healthy growth and coloration. |
| Bloodworms | High in protein, soft texture, natural source of iron for healthy blood and oxygen flow. |
| Daphnia | High in protein, natural source of essential vitamins and minerals, promotes healthy digestion. |
| Mosquito Larvae | High in protein, natural source of essential amino acids. |
| Tubifex worms | High in protein, soft texture, easy to digest. |
| Grindal worms | High in protein, natural source of essential amino acids. |
| Artemia | Rich in protein, essential amino acids, and vitamins, promoting healthy growth and coloration. |
| Flakes | Commercial food option that is easy to find and can provide a balanced diet for the fish. |
| Pellets | Commercial food option that is easy to find and can provide a balanced diet for the fish. |
Housing Requirements and What to Put in Their Tank
Harlequin rasboras are a schooling fish and should be kept in groups of at least 6 individuals. They do well in planted tanks with plenty of hiding places and open swimming areas. They also appreciate a moderate water flow and filtration.
Behavior and Temperament
The harlequin rasbora is a peaceful and non-aggressive fish. They are active swimmers and do well in community tanks with other peaceful species.
Breeding
Breeding harlequin rasboras is difficult and requires specific conditions and care. Hobbyists report the three most important factors for successful breeding is high temperatures (80F+), slightly acidic water (pH 6.0-6.4), and a diet rich in live worms.
Here is a step-by-step guide on how to breed them:
- Gather your breeding stock. It’s important to have a healthy and mature group of at least 6 individuals, with a mix of males and females. This will increase the chances of successful breeding.
- Prepare the breeding tank. The tank should be at least 20 gallons (75L) in size and have a water temperature between 78-82°F (25-28°C) with a pH range of 6.0-7.0. It’s also important to have plenty of hiding places and open swimming areas.
- Condition your fish. In order for your harlequin rasboras to be in breeding condition, they need to be well-fed and healthy. Feed them a variety of live and frozen foods such as brine shrimp, daphnia, and bloodworms.
- Introduce the males and females. Once your fish are in breeding condition, you can introduce the males and females into the breeding tank. Observe their behavior and look for courtship rituals such as chasing and flaring fins.
- Spawning and egg laying. Once the courtship rituals are observed, the females will lay their eggs in the breeding tank. The eggs will be very small and transparent, and are usually laid on plants or decorations.
- Egg care. Once the eggs have been laid, it’s important to keep the breeding tank free of debris and predators. The eggs will hatch in about 24-36 hours, depending on the temperature of the water.
- Fry care. Once the fry hatch, they will be very small and will require infusoria or newly hatched brine shrimp as food. It’s also important to keep the water clean by performing small water changes. Separate adults from young, otherwise they will cannibalize the fry. Harlequin’s have no parental instinct.
- Grow out. As the fry grow, you can start to feed them larger foods such as microworms, daphnia and crushed flakes. Keep an eye out for any signs of disease or illness and address them immediately.
Tankmates
The harlequin rasbora is a peaceful species and makes a great addition to a community tank. They do well with other peaceful fish such as Neon Tetras, Guppies, and Corydoras.
| Compatible Tankmate | Description |
|---|---|
| Neon Tetra | These vibrant little fish add a burst of color to any tank with their neon-blue and red fins. Their peaceful nature makes them an ideal companion for harlequin rasbora. |
| Guppies | These hardy and adaptable fish bring a splash of color to the tank with their vibrant hues. They are easy to breed and make for an interesting addition to a community tank. |
| Cherry Barbs | These small and active fish, known for their bright red coloration, make for a visually striking addition to a tank with harlequin rasbora. |
| Otocinclus Catfish | These little algae-eaters are a great addition to a community tank, their peaceful nature and scavenging abilities make them an ideal companion for harlequin rasbora. |
| Rummy Nose Tetra | These small and active fish, known for their distinctive red noses, make for a visually interesting addition to a tank with harlequin rasbora. |
| Corydoras Catfish | These small, hardy and peaceful scavengers are a great addition to a community tank, their active swimming style makes them a great companion for harlequin rasbora. |
| Endler’s Guppies | These small and peaceful fish, known for their bright colors, make for a visually interesting addition to a tank with harlequin rasbora. |
| Ghost Shrimp | These small and peaceful scavengers, known for their semi-transparent bodies, make for an interesting addition to a tank with harlequin rasbora. |
Diseases and Illnesses
Here are the four most common illnesses and diseases found in harlequin rasbora. We will provide a short description of each illness, symptoms to look for, and common treatments for the specific illness.
Ich (Ichthyophthiriasis)
Ich is a parasitic disease caused by a single-celled organism called Ichthyophthirius multifiliis. The symptoms of Ich include white spots on the skin, fins, and gills of the fish. The best treatment for Ich is a medication specifically designed to target Ich, such as Ich-X or API Liquid Super Ick Cure.
Fin Rot
Fin Rot is a bacterial disease that causes the fins of the fish to deteriorate and eventually fall off. The symptoms of Fin Rot include frayed or ragged fins, redness and inflammation of the fins and body. The best treatment for Fin Rot is a broad-spectrum antibiotic, such as Maracyn or Kanaplex.
Dropsy
Dropsy is a disease that causes the fish’s scales to stick out from its body, giving it a pinecone-like appearance. It is caused by a bacterial infection and can be fatal if left untreated. The symptoms of Dropsy include a swollen belly, pinecone-like scales, and lethargy. The best treatment for Dropsy is a broad-spectrum antibiotic.
Columnaris
Columnaris is a bacterial disease that causes ulcers and sores on the fish’s body. The symptoms of Columnaris include ulcers, sores, and frayed fins. The best treatment for Columnaris is a broad-spectrum antibiotic.
History and Origin
The harlequin rasbora, scientifically known as Trigonostigma heteromorpha, is a small tropical fish that is native to Southeast Asia. These fish can be found in the wild in the Malay Peninsula, Sumatra, and Borneo. They are typically found in rivers, streams, and swamps with moderate to fast-moving water.
The harlequin was first scientifically described in 1892 by the German ichthyologist, Franz Steindachner. He named the fish Rasbora heteromorpha, and it was later reclassified as Trigonostigma heteromorpha. This species was one of the first of the genus Trigonostigma to be scientifically described.
Despite its scientific discovery in 1892, the harlequin rasbora was not widely known in the aquarium hobby until the 1950s. This is when the fish was imported to the United States and Europe and became a popular addition to community tanks. They quickly gained popularity due to their vibrant orange/red and black coloration, peaceful nature, and ease of care.
One interesting fact about the harlequin rasbora is that they are known for their schooling behavior. In the wild, they can be found in large schools, and in captivity, they should be kept in groups of at least 6 individuals. This not only makes for a more visually pleasing display, but it also helps to reduce stress on the fish and promotes natural behavior.
Harlequin rasbora, the little fish with a big impact. These brightly colored fish are the perfect addition to any aquarium, adding beauty, personality, and ease of care. So whether you’re a seasoned aquarium enthusiast or a beginner just getting started, these fish are sure to delight and inspire. So go ahead, add some sparkle to your tank and see for yourself why the harlequin rasbora is a fan favorite.
Products for Harlequin Rasbora Care
| Product Name | Category | Product Link | Description |
|---|---|---|---|
| Fluval Flex 15g Aquarium | Aquarium | View on Amazon | 15-gallon all-in-one aquarium with built-in filtration, lighting, and heating. Sleek design. |
| Aqueon 10g Tank | Aquarium | View on Amazon | Durable glass aquarium, available in various sizes 10 gallons and larger. |
| Eheim Jager Aquarium Heater | Heater | View on Amazon | Adjustable, submersible aquarium heater. Shatterproof. |
| Penn-Plax Cascade 100 Power Filter | Filter | View on Amazon | Power filter appropriate for aquariums up to 15 gallons. |
| Tetra Whisper Air Pump | Air Pump | View on Amazon | Quiet and efficient air pump for aquarium. |
| Pawfly 1.5 Inch Air Stone Disc | Air stone | View on Amazon | Air stone for fine mist bubbles and water movement. |
| Zoo Med Mopani Wood | Decor | View on Amazon | Natural Mopani Wood for aquarium decoration and hiding place for fish. |
| Lifegard Aquatics Aquascaping Smoky Mountain Seiryu Stone | Decor | View on Amazon | Natural stones for aquarium decoration and pH balance. |
| New Life Spectrum Thera+A Pellets | Food | View on Amazon | High-quality, nutritious pellet food for harlequin rasbora. |
| Fluval Bug Bites | Food | View on Amazon | Freeze-dried bloodworm food for harlequin rasbora. |
| Python Aquarium Vacuum | Tool | View on Amazon | Easy-to-use vacuum for water changes, cleaning aquarium gravel and debris. |
| Java Moss | Plants | View on Amazon | Low-maintenance, hardy plant for aquarium. |
| Java Fern | Plants | View on Amazon | Low-maintenance, hardy plant for aquarium. |
| Anubias Plant | Plants | View on Amazon | Low-maintenance, hardy plant for aquarium. |
| Cryptocoryne Wendtii | Plants | View on Amazon | Low-maintenance, hardy plant for aquarium. |
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