Red Tail Shark Tank Mates - "redtail shark" by An Ta is licensed under CC BY 2.0.
Red Tail Shark Tank Mates - "redtail shark" by An Ta is licensed under CC BY 2.0.


When setting up an aquarium with a red tail shark, choosing the right red tail shark tank mates is crucial for a harmonious aquatic environment. The red tail shark, with its distinct appearance and unique behavior, requires careful consideration of compatible companions. This guide provides insights into selecting the best red tail shark tank mates, considering factors like temperament, size, and environmental needs to ensure a balanced and stress-free community tank.

Overview of the Red Tail Shark

The red tail shark, scientifically known as Epalzeorhynchos bicolor, is a striking freshwater fish celebrated for its vivid coloration and dynamic presence in aquariums. Despite its common name, it is not a true shark but belongs to the Cyprinidae family, which includes carps and minnows.

Natural Habitat

Originally found in the waters of Thailand, the red tail shark thrives in tropical freshwater environments. Their natural habitat is characterized by fast-flowing streams and rivers with a rocky substrate, often with abundant vegetation and hiding places. Unfortunately, due to habitat destruction and overfishing, this species is now considered critically endangered in the wild.

Physical Characteristics

The most distinctive feature of the red tail shark is its deep black body contrasted with a vibrant red tail, creating a visually striking appearance. They typically grow to about 4-6 inches (10-15 cm) in length in an aquarium setting. This species possesses a streamlined body shape, indicative of their ability to navigate swiftly in strong currents.


Red tail sharks are known for their semi-aggressive temperament. They are territorial and can exhibit aggression towards their own species, making it advisable to keep only one red tail shark per tank. However, they can coexist peacefully with many other species of fish, provided they have enough space and hiding places.

Activity Level

They are active swimmers and enjoy exploring their environment. A well-set-up aquarium for these fish would include plenty of space for swimming and structures like rocks, driftwood, and plants to provide refuge and territories.


In the aquarium, the red tail shark is omnivorous, feeding on a variety of foods including algae, plant matter, and small invertebrates. They are known for their appetite for algae, making them useful in controlling algae growth in the tank.

Overall, the red tail shark is a unique and vibrant addition to a freshwater aquarium. Its distinct coloration, active nature, and the need for specific care make it a favorite among aquarists who can meet its requirements for a spacious, well-structured habitat with compatible tank mates.

Tank Requirements

Creating an ideal environment for red tail sharks in a home aquarium is essential for their health and well-being. Here’s a detailed guide to setting up the perfect tank:

  • Tank Size: Red tail sharks are active swimmers and need ample space. A minimum of 55 gallons (220 liters) is recommended for a single red tail shark. This size provides enough space for swimming and territorial behavior, reducing stress and aggression.
  • Water Parameters:
  • Temperature: Maintain a tropical water temperature between 72°F and 79°F (22°C – 26°C). Consistent temperature is crucial as large fluctuations can stress the fish.
  • pH Level: The pH level should be slightly acidic to neutral, ideally between 6.5 and 7.5.
  • Water Quality: Red tail sharks require clean, well-oxygenated water. Regular water changes (about 25-30% weekly) and a robust filtration system are essential to maintain water quality and remove waste products.
  • Decoration and Layout:
  • Substrate: A dark-colored substrate can help mimic their natural habitat and also accentuate the fish’s color. Smooth gravel or sand works well.
  • Hiding Spots: Provide plenty of hiding spaces with caves, driftwood, and rock formations. This helps to reduce stress and provides territories for the red tail shark.
  • Plants: Live plants not only enhance the aesthetics of the tank but also provide additional hiding spots and help maintain water quality. Hardy plants like Java Fern, Anubias, or Amazon Sword are good choices as they can withstand the fish’s active nature.
  • Lighting and Environment: Moderate lighting is suitable for red tail sharks, simulating their natural habitat. Too much light can encourage excessive algae growth. The aquarium should also have a secure lid, as red tail sharks can jump when startled or during aggressive displays.
  • Tank Mates Compatibility: When considering tank mates, it’s important to choose species that can thrive in similar water conditions and are not too small to be considered prey. Tank mates should also not be overly aggressive or territorial to avoid conflicts.
  • Aquatic Scaping: While aesthetic, the layout should also consider the behavioral needs of the red tail shark. Open swimming areas combined with structured spaces will create a balanced environment.

By providing the right tank conditions, not only will the red tail shark thrive, but it also sets the stage for a harmonious community aquarium with compatible tank mates. Regular monitoring and maintenance of these conditions are crucial for the health of all aquarium inhabitants.

Compatibility Considerations

When considering red tail shark tank mates, several key factors must be taken into account to ensure a harmonious and healthy aquarium environment. These factors include temperament, size, and activity level of both the red tail sharks and their potential companions.

  • Temperament: Red tail sharks are known for their semi-aggressive and territorial nature. They tend to be more aggressive towards fish of their own kind or those that resemble their body shape and size. It’s important to select tank mates that are neither too aggressive to provoke the red tail shark nor too timid to be bullied by it. Ideally, tank mates should be peaceful or mildly assertive to maintain balance.
  • Size and Physical Attributes: The size of potential tank mates is a critical consideration. Fish significantly smaller than the red tail shark might be seen as prey, while much larger fish could intimidate or harm the shark. The ideal tank mate should be of a similar or slightly larger size. Additionally, avoid fish with long fins or delicate features, as they might become targets for nipping.
  • Activity Level and Swimming Regions: Red tail sharks are active swimmers and tend to establish territories near the bottom of the tank. It’s preferable to choose tank mates that occupy different levels of the tank to minimize competition and territorial disputes. For instance, mid-water and top-dwelling species can be good companions, ensuring all areas of the tank are utilized and reducing the likelihood of conflict.
  • Environmental Needs: Tank mates should have similar requirements in terms of water parameters (temperature, pH, hardness) and environmental conditions. This compatibility ensures that all fish thrive without the need for compromise on essential aspects like water quality and tank setup.
  • Dietary Compatibility: While red tail sharks are not overly demanding in terms of diet, it’s important to ensure that all fish in the tank can coexist without competition for food. Tank mates should have similar dietary needs and feeding behaviors to ensure that all fish receive adequate nutrition.
  • Experience Level of the Aquarist: Some fish might be theoretically compatible with red tail sharks but require experienced care. Beginners should opt for hardier, less demanding species, while experienced aquarists might manage more sensitive or challenging combinations.

The key to successful compatibility lies in choosing red tail shark tank mates that can live in harmony with the red tail shark’s temperament, size, and activity level, while also thriving under similar environmental and dietary conditions. Careful consideration of these factors will contribute to a balanced, stress-free aquarium where both the red tail sharks and their tank mates can flourish.

Red Tail Shark Tank Mates - "redtail shark" by An Ta is licensed under CC BY 2.0.
Red Tail Shark Tank Mates – “redtail shark” by An Ta is licensed under CC BY 2.0.

Recommended Red Tail Shark Tank Mates

When selecting tank mates for red tail sharks, it’s crucial to choose species that are compatible in terms of water parameters, temperament, and size. Here’s a list of species known to be good companions for red tail sharks:

  • Barbs: Tiger barbs, rosy barbs, and cherry barbs are good choices. These active and hardy fish can match the red tail shark’s energy levels. However, in smaller groups, they may nip fins; larger groups are less likely to exhibit this behavior.
  • Danios: Zebra danios and pearl danios are excellent companions. They are quick swimmers and occupy the upper levels of the tank, minimizing interactions with the bottom-dwelling red tail shark.
  • Rainbowfish: Vibrantly colored species like the rainbowfish can be a great addition. These peaceful and active fish swim in the mid to upper levels of the tank.
  • Loaches: Kuhli loaches or yoyo loaches are suitable due to their peaceful nature. They are nocturnal and have different feeding times than the red tail shark, reducing food competition.
  • Gouramis: Dwarf gouramis and pearl gouramis are suitable tank mates. They generally stay in the middle to upper parts of the tank, away from the red tail shark’s territory.
  • Larger tetras: Congo tetras and black skirt tetras can be appropriate as they are relatively larger and robust enough to coexist with the red tail shark.
  • Cichlids: Some African cichlids can be compatible, but careful selection is necessary. Avoid aggressive or highly territorial cichlids.
  • Bala sharks: Despite their name, Bala sharks are peaceful and can grow to a considerable size, making them suitable companions for the red tail shark in larger tanks.
  • Plecos: Plecos, especially smaller species, can be a good match as they are bottom dwellers and focus on algae and detritus, reducing competition for food.
  • Swordtails and platies: These are peaceful, easygoing fish that typically swim in the upper part of the aquarium, reducing the likelihood of conflict with the red tail shark.

It’s important to monitor the aquarium closely when introducing new tank mates to ensure a harmonious environment, especially during the initial stages. Success in maintaining a community tank also hinges on providing ample space, adequate hiding spots, and maintaining optimal water conditions for all species.


In conclusion, selecting suitable red tail shark tank mates is a vital step in creating a thriving aquarium community. By understanding the specific requirements and behaviors of the red tail shark and its potential companions, aquarists can establish a harmonious and visually appealing tank. Remember, the key to a successful red tail shark tank lies in careful planning, consideration of compatibility, and ongoing observation to maintain a healthy and balanced aquatic ecosystem.