Roseline Shark (Sahyadria denisonii) - 2"-3" - Live Fish

The Roseline Shark, also known as the Red-Line Torpedo Barb or Red-Finned Shark, is a striking and popular species of freshwater fish, scientifically known as Sahyadria denisonii. Despite its common name, it is not a true shark but rather a type of barb, and its vibrant colors and active nature make it a favorite among aquarium enthusiasts. Native to the rivers of southern India, this species is often admired for its eye-catching appearance and relatively easy care.

Here’s a detailed look at the Roseline Shark Barb:

1. Appearance

• Coloration: The Roseline Shark has a distinctive and vibrant appearance. It has a silvery or golden body with two prominent red or orange horizontal stripes that run along its body, one along the upper body and another along the lower part. The tail fin is bright red, which further accentuates its colorful appearance.
• Size: The Roseline Shark is a medium-sized fish, growing to about 4-6 inches (10-15 cm) in length. While not excessively large, it is active and requires adequate space in the aquarium.
• Shape: It has a sleek, elongated, torpedo-shaped body, with a slightly compressed shape. Its fins are relatively short and triangular in shape, contributing to its overall streamlined, shark-like appearance.
• Eyes: The Roseline Shark has sharp, dark eyes, which contribute to its alert and lively nature.

2. Temperament

• Semi-aggressive: Despite its name, the Roseline Shark is not a true shark, but it can be somewhat territorial, especially with other fish of similar size or shape. While not excessively aggressive, it may show signs of territoriality, particularly towards other fish that resemble it, such as other barbs or similarly shaped species.
• Active and Energetic: Roseline Sharks are known for being active and energetic swimmers. They are often seen darting around the tank, exploring their environment. They are best kept in groups of at least 6 individuals, as they tend to thrive in schools.
• Social with Peaceful Fish: In general, they are peaceful towards other non-aggressive species, though they may become more territorial with fish that invade their personal space. It’s best to house them with peaceful species that won't compete for space or intimidate them.

3. Habitat

• Tank Size: Due to their active swimming habits and potential size, Roseline Sharks require a minimum of 30 gallons (113 liters) for a small group. Larger tanks are better, as they allow for more swimming space and a more stable environment.
• Water Conditions: Roseline Sharks thrive in slightly acidic to neutral water, with a pH range of 6.5 to 7.5. They prefer temperatures between 72-79°F (22-26°C), with stable water conditions. They are quite adaptable to different water hardness levels, but slightly soft to moderate hardness is ideal.
• Substrate and Decorations: A fine gravel or sand substrate is best. The tank should also have plenty of plants (preferably soft-leaved), driftwood, and rocks to mimic their natural riverine habitat. Although they like some cover, they also need open spaces to swim freely.
• Filtration: Good filtration is essential to maintain clean, oxygenated water. Roseline Sharks are sensitive to poor water quality, so regular water changes and proper filtration are crucial for their health.

4. Diet

• Omnivorous: Roseline Sharks are omnivores, and they have a broad diet. They will eat:
  • High-quality flakes or pellets (ensure they are appropriate for medium to large fish).
  • Live or frozen foods, including bloodworms, brine shrimp, or daphnia.
  • Vegetable matter, such as blanched spinach, zucchini, or lettuce.
  • Algae or spirulina-based foods, which can also be added to their diet.
• Feeding Frequency: Feed them 2-3 times a day in small portions. Be sure not to overfeed, as uneaten food can pollute the water. Providing a varied diet will help maintain their health and vibrant coloration.

5. Behavior and Care

• Active and Social: These fish are highly active, and they require a tank that allows them to swim freely. They will often explore all areas of the tank, especially the middle and top levels. Roseline Sharks are also social and do well when kept in groups, which helps reduce stress and promotes their natural behaviors.
• Lifespan: Roseline Sharks have a relatively long lifespan for a species of this size, living up to 5-7 years in captivity with proper care.

6. Breeding

• Breeding in Captivity: Breeding Roseline Sharks in captivity is quite rare, as they typically need specific conditions to spawn. In the wild, they breed during the monsoon season when the water is flooded, and temperatures rise slightly. However, there is little documented success in breeding them in home aquariums.
• Egg Layers: Roseline Sharks are egg-layers, and breeding would require a separate breeding tank. Females will lay eggs, which will then be fertilized by males. Once the eggs hatch, the fry are relatively small and require infusoria or finely crushed foods for their first meals.

7. Tankmates

• Suitable Tankmates: Roseline Sharks are generally peaceful with other non-aggressive species. Good tankmates include:
  • Other medium-sized barbs like Odessa Barbs or Cherry Barbs.
  • Tetras, such as Neon Tetras or Rummy Nose Tetras.
  • Rasboras, Corydoras catfish, and small peaceful cichlids.
  • Livebearers, such as Guppies or Mollies.
• Avoid Aggressive Fish: They may become stressed or territorial when housed with more aggressive fish, such as larger cichlids or other predatory species.

8. Considerations

• Territoriality: While not overly aggressive, Roseline Sharks can be territorial and may show aggression towards similarly sized or shaped fish. It's important to avoid overcrowding and provide sufficient hiding places.
• Water Quality: These fish are sensitive to water quality, so maintaining a clean tank with good filtration and regular water changes is essential.
• Schooling Behavior: Like other schooling fish, Roseline Sharks feel more secure in groups. It is highly recommended to keep at least 6 individuals together to promote their natural social behavior and reduce stress.

The Roseline Shark is a beautiful, active, and peaceful species that makes an excellent addition to community aquariums, especially when housed in schools. Its striking appearance, vibrant colors, and lively behavior make it a standout fish in any tank. While they are relatively easy to care for, it is essential to provide them with a spacious tank, good water quality, and compatible tankmates to ensure they thrive. These fish are a delight to watch as they explore their environment, and with proper care, they can live for many years in a well-maintained aquarium.