Denison Barb (Roseline Shark) – Care, Feeding and Full Details!

The Denison Barb, fondly referred to as Roseline Sharks, are undeniably enchanting, energetic, and lively additions to any aquarium. Our initial encounter with this species left us smitten, inspiring us to share our experience and knowledge with other passionate aquarists.

In your quest for an extraordinary display of color in your home aquarium, the Denison Barb (scientifically known as Sahyadria denisonii) is a worthwhile freshwater species to consider.

Indigenous to the rapid rivers and streams of Western India, this fish has garnered immense popularity among the fish-keeping community.

Note: In response to their popularity and consequential habitat changes threatening wild populations, local governments have imposed export bans on the fish. As a result, most specimens available in the market are commercially bred.

These fish have earned many monikers – you might spot them labelled as Roseline Shark, Red-Line Torpedo Barb, or Miss Kerala. Regardless of the title, their stunning appearance is unmistakable and irreplaceable.

These fish prove to be excellent companions for large aquariums. Their vibrant coloration and active lifestyle promise years of joy for aquarists.

Our comprehensive guide explores the full scope of Denison Barb care, encompassing elements such as ideal tank mates, diet, lifespan, size, and more crucial factors for their wellbeing.

Quick Stats About Denison Barb (Roseline Shark)

Care Level: Easy
Temperament: Peaceful
Color: Silver with patches of red and yellow
Lifespan: Up to 5 years
Size: Up to 6 inches
Diet: Omnivore
Family: Cyprinidae
Minimum Tank Size: 55 gallons
Tank Setup: Freshwater with plants and open swimming space
Compatibility: Peaceful community

The world of aquaculture presents the Denison Barb (Roseline Shark) as a precious gem, admired by aquarists worldwide for its vivid colors and dynamic nature.

Let’s delve deeper into understanding this remarkable species.

Appearance of Denison Barb (Roseline Shark)

The Denison Barb, also widely known as the Roseline Shark, is a spectacle to behold. Flaunting a vibrant color palette, these freshwater fish transform any aquarium into a lively and stunning display.

Their bodies, long and streamlined, mimic the form of a torpedo, contributing to their agility in water.

The base color of the Denison Barb is predominantly silver, sometimes showcasing undertones of yellow or gold, based on lighting conditions.

A distinguishing feature of the Roseline Shark is the dual stripes running along the length of their bodies. A solid black stripe extends from the tip of the snout to the base of the caudal fin.

Above it, a striking red stripe starts from the snout, runs through the eye, and fades around the midsection of the fish, presenting a stunning contrast to the silver base.

In addition, the front of the dorsal fin flaunts a vibrant red band, while the tailfin exhibits black and yellow stripes at its forked ends.

A mature Denison Barb often displays an enchanting shade of emerald green on its head, adding to its appeal. A slight difference in size and color intensity between males and females is noted, with females often larger and slightly duller.

Natural Habitat of the Denison Barb (Roseline Shark)

The Denison Barb, or Roseline Shark, is native to the fast-flowing rivers and streams of Western India, mainly in Kerala and Karnataka.

They thrive in oxygen-rich waters teeming with plant life, a testament to the pristine conditions of their natural habitats.

In the wild, these fish often live in the middle to upper areas of the water column, using their torpedo-shaped bodies to swiftly navigate the currents.

Origin and Distribution

This fascinating species was first discovered in 1865 and named after the then Governor of Madras, Sir William Denison. The fish has several other names, including Red-Line Torpedo Barb and Miss Kerala, each showcasing a unique aspect of the fish’s appearance or origin.

The Denison Barbs are endemic to the Western Ghats of India, particularly in Chalakudy River and Achankovil river systems.

The Western Ghats is a biodiversity hotspot, housing a vast array of flora and fauna, including our brilliant Denison Barb.

Due to their captivating beauty and playful nature, Denison Barbs have gained tremendous popularity in the fishkeeping hobby globally. It’s worth noting that the wild populations are now under threat due to habitat loss and over-fishing.

However, to combat this, local governments have implemented strict regulations on their export, leading to a rise in commercially bred specimens for the aquarium trade.

Growth, Size & Lifespan

In a well-maintained aquarium setting, Denison Barbs can grow up to six inches in length, with their vivid colors and distinct patterns becoming more pronounced as they mature.

These fish, with their significant size and radiant hues, easily become the highlight of any tank, catching the eye of every observer.

Their growth rate is fairly consistent, reaching their full size in a matter of months. When provided with the appropriate care, including a balanced diet and a well-managed habitat, the lifespan of a Denison Barb or Roseline Shark can extend up to five years, sometimes even longer.

While these figures can be influenced by various factors, with diligent care, your Denison Barb can live a full, active, and enjoyable life.

Mastering the care of the Denison Barb, or the Roseline Shark, as it’s fondly known, is a journey that calls for dedication and understanding.

Yet, the reward is truly gratifying as you witness the captivating charm of these freshwater marvels unfolding right before your eyes in your very own aquarium.

Dive into the fascinating world of the Denison Barb, also affectionately known as the Roseline Shark. This freshwater fish species boasts an engaging persona and distinctive habitat preferences that make them an irresistible choice for hobbyists.

Let’s delve into their behavior, temperament, and aquarium setup necessities.

Denison Barb Behavior and Temperament

Denison Barbs are admired for their active and peaceful temperament. With their graceful swimming style and playful agility, they add a dynamic and lively feel to any aquarium setup.

They’re a schooling fish and thrive best when kept in groups of at least six. In smaller groups, they may feel stressed, which can lead to subdued colors and a decrease in activity.

Despite their shark moniker, Roseline Sharks are far from aggressive. They coexist well with other fish species, proving to be harmonious tank mates.

They’re predominantly mid to top level swimmers, often seen zipping across the tank in a flurry of color.

The Perfect Denison Barb (Roseline Shark) Tank Setup

Creating the ideal tank setup for your Denison Barb can significantly enhance their health and vitality.

Let’s discuss this in more detail.

Tank Size

Given their active nature and size, Denison Barbs require a spacious tank to thrive. A tank size of at least 55 gallons is recommended for a small school. It provides ample room for them to swim and explore, imitating their natural riverine habitat.


A substrate of fine sand or small, rounded gravel works best for Roseline Sharks. Darker colors can help mimic their natural habitat and make their colors pop.

Decorations and Hiding Spots

To recreate their natural environment, use river rocks, driftwood, and a variety of aquatic plants. This offers hiding spots and promotes a sense of security for the fish. Ensure there’s still plenty of open swimming space for the active Roseline Shark.

Water Parameters

As a tropical freshwater species, the Denison Barb prefers water temperatures between 72°F and 79°F. The pH should be slightly acidic to neutral (6.5 to 7.5), and the hardness should be within 5-15 dGH.

Filtration and Aeration

Due to their origin in fast-flowing waters, Denison Barbs thrive in well-oxygenated tanks with moderate to high water movement. Choose a high-quality filter that can keep the water clean and stimulate water flow.


Roseline Sharks are not picky about lighting. Moderate lighting suits them just fine, although they appreciate some darker spots provided by plants or decorations.

Tank Mates

Given their peaceful nature, Denison Barbs can coexist well with a variety of tank mates. Other peaceful mid-to-top dwelling fish of similar size make excellent companions. Avoid aggressive or territorial species that might cause stress.


As omnivores, Denison Barbs have a diverse diet. A mix of high-quality flake or pellet food, supplemented with fresh, freeze-dried or frozen foods like brine shrimp or bloodworms, will keep them healthy and their colors vibrant.

Catering to the needs of the Denison Barb, or Roseline Shark, is a rewarding endeavor. The right tank setup and understanding of their behavior ensure a thriving, colorful, and lively community tank that brings a slice of nature right into your living room.

Denison Barb: The Roseline Shark’s Tank Maintenance

Creating an ideal living environment for Denison Barb doesn’t end at tank setup. Ensuring their wellbeing requires regular maintenance to keep the tank clean, stable, and safe.

Proper tank maintenance is vital to keeping your Denison Barb (or Roseline Shark) healthy and active. It includes regular water changes, cleaning the tank and decorations, maintaining the filter, and monitoring your fish’s health.

Let’s delve into these practices and their significance in the world of aquarium care.

Regular Water Changes

Water changes are a key aspect of tank maintenance. For the Roseline Shark, replacing 20-25% of the tank water every week is recommended.

This practice helps to dilute the buildup of harmful substances, like nitrates, and replenishes essential minerals. Remember to dechlorinate and match the temperature of the new water to the existing tank water to avoid stress to the fish.

Cleaning the Tank and Decorations

Algae and waste buildup over time can negatively impact your Denison Barb’s health. Cleaning the tank and decorations every few weeks helps prevent this buildup.

You can gently scrub the tank walls and decorations with an algae scrubber. However, avoid using soap or chemical cleaners, as they can be harmful to fish.

Filter Maintenance

The filter plays an integral role in maintaining water quality. It removes waste and harmful chemicals while providing oxygenation.

Regular maintenance, such as replacing the cartridges and cleaning the filter, helps keep it working efficiently. Always rinse filter parts with the tank water to preserve the beneficial bacteria essential for your Denison Barb’s health.

Monitor Fish Health

Regularly observe your Roseline Shark for signs of illness. Look for changes in behavior, appetite, color, or physical abnormalities.

Early detection can often be the key to successful treatment. Remember, a healthy Denison Barb is active, brightly colored, and has a good appetite.

Maintaining a clean, stable tank environment is crucial for the wellbeing of your Denison Barb. With regular water changes, tank cleaning, filter maintenance, and health monitoring, you can ensure your Roseline Shark thrives in a safe and healthy home.

This routine may seem like a lot of work, but the reward of seeing your vibrant and energetic Denison Barbs happily swimming around is worth every bit of it.

Acclimating Denison Barb

Acclimation is a crucial step when introducing your Denison Barb to a new tank environment. This process helps to slowly adapt the fish to the water parameters of the new tank, reducing stress and preventing health problems.

It’s best to follow the drip method for acclimation.

Firstly, float the bag containing your new Denison Barb in the tank for about 15 minutes to match the temperatures. Then, add a small amount of tank water to the bag every 10 minutes for an hour.

This allows the Roseline Shark to adjust to the new water chemistry gradually. Finally, gently release the fish into the tank using a net.

Denison Barb Diet and Feeding

Proper nutrition is integral to the health and vibrancy of your Denison Barb. These fish are omnivores, meaning they eat both plant and animal matter.

Here are some important aspects to consider:

Variety in Diet

Provide a variety of foods to ensure a balanced diet. This could include high-quality flake foods or pellets, as well as live or frozen foods such as brine shrimp, daphnia, and bloodworms.

Occasional servings of vegetable matter, like boiled zucchini or spinach, can also be beneficial.

Feeding Frequency

Denison Barbs should typically be fed twice a day. Only provide as much food as they can consume within two to three minutes to avoid overfeeding.

Dietary Supplements

Consider adding vitamin and mineral supplements to your Denison Barb’s diet to enhance their overall health and color. These can often be mixed into their food.

Observing Eating Habits

Regularly observe your Roseline Sharks during feeding times. This can give you insight into their health, as changes in appetite may indicate illness.

Understanding your Denison Barb’s dietary needs and providing them with a varied, nutrient-rich diet will significantly contribute to their health, lifespan, and vibrancy. Combine this with careful acclimation and consistent tank maintenance, and your Roseline Sharks will be set up for a healthy, happy life in their aquatic home.

Denison Barb Tank Mates: Friends and Foes

The Denison Barb, often referred to as the Roseline Shark, is a sociable fish species that loves to be in a group.

But when it comes to adding other species to the tank, you need to choose wisely.

To create a harmonious environment, you need to choose tank mates with similar temperaments and water parameter requirements.

Here are some species that tend to get along well with Denison Barbs:

  1. Tetras: Known for their peaceful nature, Tetras (like Black Skirt Tetra or Cardinal Tetras) are excellent choices.

  2. Rasboras: These fish are peaceful and thrive in similar conditions, making them a good match.

  3. Gouramis: The gentle-natured Gouramis can peacefully coexist with Denison Barbs.

  4. Angelfish: Their peaceful demeanor and similar water needs make them compatible with Roseline Sharks.

  5. Rainbowfish: Known for their friendly nature and stunning coloration, Rainbowfish are an excellent choice.

  6. Corydoras Catfish: These bottom-dwelling fish can add diversity to your tank while living peacefully with Denison Barbs.

  7. Plecos: Another species of bottom-dwellers, Plecos won’t disrupt the Denison Barb’s space.

  8. Loaches: Fish like the Kuhli Loach or Clown Loach can make good companions.

Tank Mates to Avoid

While many species can peacefully coexist with the Denison Barb, some should be avoided.

These include:

  1. Cichlids: Most types of Cichlids are aggressive and can stress out your Roseline Sharks.

  2. Oscars: Oscars are territorial and could attack Denison Barbs.

  3. Bettas: Known for their aggressive tendencies, Betta fish aren’t a good match.

  4. Red Tail Sharks: They can be territorial and aggressive towards Denison Barbs.

  5. Goldfish: Goldfish prefer different water conditions, making them unsuitable tank mates.

Breeding Denison Barbs and Caring for the Fry

Breeding Denison Barbs can be a challenge, but with the right approach, it’s possible to raise these beautiful fish in your aquarium.

Denison Barbs are egg scatterers, meaning they lay their eggs and move on, without any parental care.

Here are some steps to induce breeding:

  1. Set up a separate breeding tank: This helps protect the eggs and fry from being eaten by other fish.

  2. Maintain ideal water conditions: A slightly lower pH and temperature can induce spawning.

  3. Provide a varied, high-quality diet: This will help prepare the fish for breeding.

  4. Identify and pair males and females: Females are typically larger and rounder than males.

  5. Watch for spawning behavior: This includes chasing and more active swimming.

Fry Care

After the Denison Barbs lay eggs, the parents should be removed to prevent them from eating the eggs.

Here are some tips for fry care:

  1. Use a sponge filter: It provides gentle filtration that won’t harm the delicate fry.

  2. Feed them appropriate food: Newly hatched brine shrimp is an ideal first food for the fry.

  3. Perform regular water changes: This helps to keep the water clean and free of toxins.

  4. Monitor their growth: As they mature, you can gradually introduce them to the main tank.

Breeding Denison Barbs can be a rewarding experience. With care and patience, you can raise the next generation of this stunning species.

Denison Barb: Signs of Stress

Your Denison Barb, or Roseline Shark, has a dynamic personality. But, how can you tell if it’s under stress? Understanding these signs is critical for your fish’s wellbeing.

  1. Changes in Color: A healthy Denison Barb has vibrant colors. If your fish’s colors appear dull or faded, it could be a sign of stress.

  2. Erratic Swimming: If your Roseline Shark is swimming erratically or pacing the tank, it might be feeling distressed.

  3. Loss of Appetite: A sudden decrease in appetite can indicate stress or illness.

  4. Hiding: While some hiding is normal, excessive seclusion could suggest discomfort.

  5. Gasping for Air: If your Denison Barb is at the water surface gasping for air, this can be a serious sign of stress, often related to water quality.

Common Health Issues and Treatments for Denison Barbs

Like any living creature, Denison Barbs can encounter health issues.

Here are some common problems and their treatments:

  1. Ich: This parasitic disease can cause white spots on the fish’s body. Raise the water temperature slowly to about 86 degrees Fahrenheit and use an over-the-counter Ich treatment.

  2. Fin Rot: This bacterial infection can lead to frayed or decaying fins. Improve water quality and consider antibiotic treatments.

  3. Dropsy: A bacterial infection causing bloating. This is often difficult to treat, but antibiotics may help in the early stages.

  4. Swim Bladder Disease: This condition can cause swimming difficulties. Adjusting the diet and improving water quality can often help.

Always consult a vet or professional if you’re unsure about your fish’s health.


Additional Tips for a Healthy Aquarium

  1. Regular Testing: Test the water parameters regularly to ensure they’re within the ideal range for your Roseline Sharks.

  2. Varied Diet: A varied diet is essential for your Denison Barbs’ health. Include a mix of commercial and fresh foods.

  3. Tank Size: Make sure your tank is large enough to comfortably house all its inhabitants.

  4. Peaceful Environment: Limit noise and disturbances around the aquarium to reduce stress for your fish.

Should You Get a Denison Barb for Your Aquarium?

Deciding to bring a Denison Barb into your aquarium is a commitment. This attractive, lively fish can bring joy and beauty to your tank. However, they require a good-sized tank, clean water, and companionship, given their schooling nature.

If you’re prepared for the commitment and eager to create a vibrant underwater world, a Denison Barb could be a perfect choice. It’s a rewarding journey that opens up the magic of the aquatic realm right in your home.

Remember, every Roseline Shark you nurture adds to the love for these amazing creatures, aiding their conservation and appreciation.

Denison Barb: Conservation Status

The Denison Barb, or Roseline Shark, is classified as “Endangered” on the IUCN Red List. This status is due to overfishing for the aquarium trade and habitat destruction in its native range.

Conservation efforts are ongoing to protect these stunning fish in their natural habitats.

Availability & Pricing

Denison Barbs are widely available in pet stores and online due to their popularity. However, due to their endangered status, ensure you’re buying from a reputable supplier who sources sustainably bred fish.

Pricing varies depending on size and age, but generally, you can expect to pay between $15 to $30 per fish.

Frequently Asked Questions About Denison Barbs

1. How long do Denison Barbs live?

With proper care, a Denison Barb can live up to 8 years in captivity.

2. Can Denison Barbs live in a community tank?

Yes, Denison Barbs are peaceful and do well in community tanks with similar-sized, non-aggressive fish.

3. How many Denison Barbs should be kept together?

It’s best to keep a group of at least six Denison Barbs as they are schooling fish and thrive in groups.

4. What do Denison Barbs eat?

They eat a varied diet, including flake food, freeze-dried food, and live or frozen foods such as brine shrimp and bloodworms.

5. Do Denison Barbs need a heater?

Yes, as tropical fish, they need a heater to maintain a water temperature between 60-77°F (15-25°C).


Denison Barbs, or Roseline Sharks, are engaging, energetic, and vibrant additions to any aquarium. Their care requirements are moderate, and they provide an excellent opportunity for hobbyists to contribute to the conservation of an endangered species.

Though they need specific conditions and a suitable tank environment, their striking appearance and active behavior make the effort worthwhile.

So, if you’re looking to create a vibrant community in your aquarium, the Denison Barb is a choice that’s not just good for you, but also beneficial for the broader ecosystem.