Introduction

The Glass Bloodfin Tetra (Prionobrama filigera) is an elegant and peaceful freshwater fish that adds a touch of subtle beauty to any aquarium. Known for its translucent, glass-like body and the striking red hues on its tail fin, this species has become a favorite among beginner and experienced aquarists alike. The Glass Bloodfin Tetra’s peaceful temperament and shoaling behavior make it ideal for community tanks, and its relatively simple care requirements make it accessible to aquarists of all skill levels.

Native to the slow-moving rivers and streams of South America, particularly in the Amazon Basin, the Glass Bloodfin Tetra is well-suited for densely planted aquariums that replicate its natural habitat. These fish are active swimmers, often schooling together in mid-levels of the tank, creating an eye-catching display as they move in unison. While hardy and adaptable, they still require a proper setup, a balanced diet, and compatible tank mates to thrive.

This comprehensive care guide will cover everything you need to know about keeping Glass Bloodfin Tetras, from tank setup and water conditions to diet, behavior, and compatibility with other species.

1. Species Overview

1.1 Scientific Classification

• Scientific Name: Prionobrama filigera
• Common Name: Glass Bloodfin Tetra, Glass Tetra
• Family: Characidae (Tetra family)
• Origin: South America (Amazon Basin, particularly Brazil, Peru, and Colombia)
• Lifespan: 3-5 years with proper care
• Size: Up to 2.5 inches (6 cm)
• Care Level: Easy
• Temperament: Peaceful
• Tank Level: Mid-level swimmer

1.2 Physical Appearance

The Glass Bloodfin Tetra is a small, slender fish characterized by its translucent body, which gives it a “glass-like” appearance. This transparency allows you to see the internal organs of the fish, a feature that adds to its unique and fascinating appeal. The most striking feature of the Glass Bloodfin Tetra is its red-colored tail fin, which contrasts beautifully with its otherwise clear body. The dorsal, anal, and pelvic fins are typically translucent as well, contributing to the fish’s delicate and elegant look.

As juveniles, these fish exhibit even more pronounced transparency, but as they mature, the red on the tail fin becomes more vibrant. Their small size, combined with their active and peaceful nature, makes them an excellent addition to community aquariums, where they can interact harmoniously with other species.

2. Natural Habitat

2.1 Geographic Origin

Glass Bloodfin Tetras are native to the freshwater rivers and streams of South America, particularly in the Amazon Basin regions of Brazil, Peru, and Colombia. These fish inhabit slow-moving rivers and densely vegetated streams where they can find plenty of cover in the form of aquatic plants, roots, and submerged debris. The natural environment of Glass Bloodfin Tetras consists of soft, slightly acidic water with relatively stable temperatures and low water movement.

In the wild, they are often found in large schools, foraging for small insects, plant matter, and other organic debris. Their native habitat is characterized by dim lighting, thanks to the dense canopy of the rainforest, which filters the sunlight and creates a more subdued environment for these small fish.

2.2 Water Conditions in the Wild

In their natural habitat, Glass Bloodfin Tetras live in soft, slightly acidic water with low mineral content. The water in the Amazon Basin is warm and stable in terms of temperature, with abundant plant life and plenty of hiding spots for the tetras. This provides them with an ideal environment to form schools and move freely while foraging for food.

To replicate these conditions in a home aquarium, it’s important to provide water that is:

• Temperature: 72°F to 82°F (22°C to 28°C)
• pH: 6.0 to 7.5 (slightly acidic to neutral)
• Water hardness: 2 to 10 dGH (soft to moderately hard water)
• Ammonia and Nitrites: 0 ppm (both should always be undetectable)
• Nitrate levels: < 20 ppm (lower levels are preferable)

Maintaining stable water parameters is crucial for the health and longevity of Glass Bloodfin Tetras, as they are sensitive to fluctuations in water quality.

3. Tank Setup

3.1 Tank Size

Although Glass Bloodfin Tetras are small fish, they are active swimmers that prefer to be kept in groups of at least six to eight individuals. For this reason, a minimum tank size of 20 gallons (75 liters) is recommended to provide enough swimming space for a small school. However, larger tanks (30 gallons or more) are ideal if you plan to keep a larger school or house them with other species.

A longer tank with plenty of horizontal swimming space is preferable for these tetras, as they will spend most of their time darting around the mid-levels of the aquarium in unison with their school.

3.2 Water Parameters

Maintaining stable and appropriate water parameters is crucial for the well-being of Glass Bloodfin Tetras. These fish thrive in soft, slightly acidic water, and they are more comfortable in environments that closely replicate the conditions of their native habitat. The ideal water parameters for Glass Bloodfin Tetras are:

• Temperature: 72°F to 82°F (22°C to 28°C)
• pH: 6.0 to 7.5 (slightly acidic to neutral)
• Water hardness: 2 to 10 dGH (soft to moderately hard)
• Ammonia and Nitrites: 0 ppm (both should always be undetectable)
• Nitrate levels: < 20 ppm (lower levels are ideal)

Regular water changes (about 20-25% weekly) are essential to maintain high water quality and ensure a stable environment for the tetras. Using a reliable test kit to monitor ammonia, nitrite, nitrate, and pH levels will help keep the water within the appropriate range.

3.3 Filtration and Water Flow

Glass Bloodfin Tetras originate from slow-moving rivers and streams, so they prefer tanks with gentle water movement. A good filtration system is necessary to maintain clean water, but the flow should not be too strong, as this can cause stress for the fish. A hang-on-back filter or sponge filter with an adjustable flow rate is ideal for creating a calm environment with adequate filtration.

In addition to mechanical and biological filtration, it’s important to avoid over-filtration, as excessive water flow can disrupt the natural behavior of the tetras. Gentle water movement mimics their natural habitat and allows them to swim freely without expending too much energy.

3.4 Tank Décor and Aquascaping

Glass Bloodfin Tetras thrive in planted aquariums that offer plenty of cover and mimic their natural environment. Dense vegetation provides hiding spots and security, making the tetras feel more comfortable and less stressed. Aquascaping with live plants, driftwood, and rocks will help create an aesthetically pleasing and functional habitat for these fish.

Here are some tips for creating the ideal tank setup for Glass Bloodfin Tetras:

• Live Plants: Use a variety of live plants, such as Amazon swords, Java fern, Anubias, and Vallisneria, to create dense, natural-looking vegetation. These plants will help create shaded areas where the tetras can retreat when they feel threatened.
• Substrate: A dark, soft substrate such as fine sand or plant-friendly gravel will mimic the riverbeds they inhabit in the wild. Darker substrates also enhance the tetras’ colors, making the red on their tail fins stand out more.
• Driftwood and Rocks: Adding driftwood, rocks, and caves will provide additional hiding spots and enhance the natural look of the tank. These decorations also contribute to a sense of security for the fish, helping them exhibit more natural behaviors.
• Lighting: Glass Bloodfin Tetras prefer dim lighting, as they are accustomed to shaded environments in the wild. You can achieve this by using floating plants or adjustable lighting to reduce the intensity of the light in the tank.

By creating a well-planted and carefully aquascaped environment, you will help reduce stress for your Glass Bloodfin Tetras and encourage them to display their natural shoaling behavior.

4. Diet and Feeding

4.1 Natural Diet

In the wild, Glass Bloodfin Tetras are omnivorous, feeding on a variety of small invertebrates, plant matter, and organic debris found in their environment. They are opportunistic feeders, foraging for food in the water column and among plant roots. Their natural diet includes small insects, insect larvae, algae, and detritus.

4.2 Feeding in Captivity

In captivity, Glass Bloodfin Tetras should be provided with a varied diet to ensure they receive all the necessary nutrients for optimal health and vibrant coloration. A balanced diet of high-quality commercial foods, live or frozen foods, and plant matter will keep them healthy and active.

Here are some recommended food options for Glass Bloodfin Tetras:

• Flakes and Pellets: High-quality tropical fish flakes or micro-pellets designed for small fish should form the staple of their diet. Look for foods that contain a good balance of proteins and plant matter to meet their omnivorous dietary needs.
• Live or Frozen Foods: Supplement their diet with live or frozen foods such as daphnia, brine shrimp, bloodworms, and mosquito larvae. These protein-rich foods will help promote growth, enhance coloration, and mimic their natural feeding habits.
• Vegetable Matter: Occasionally offer blanched vegetables such as spinach or zucchini to provide additional nutrients and fiber. Algae-based foods or spirulina flakes can also be included as part of their diet.

Feed your Glass Bloodfin Tetras 2-3 times per day, offering only as much food as they can consume within a few minutes. Be sure to avoid overfeeding, as uneaten food can lead to poor water quality and health issues.

4.3 Tips for Encouraging Feeding Behavior

Glass Bloodfin Tetras are generally eager feeders and will readily accept a variety of foods. To encourage their natural foraging behavior, you can scatter the food across the water’s surface or in different areas of the tank. This will simulate their wild feeding habits and help keep them engaged and active.

It’s important to maintain a balanced diet that includes both protein and plant matter, as this will support their overall health, vibrant colors, and longevity.

5. Behavior and Compatibility

5.1 General Behavior

Glass Bloodfin Tetras are peaceful, social fish that thrive when kept in groups of six or more. They are highly active and spend most of their time swimming in the mid-levels of the tank, often schooling together in tight formations. This shoaling behavior is not only visually appealing but also helps reduce stress and promote a sense of security among the fish.

These tetras are non-aggressive and do not exhibit territorial behavior, making them ideal candidates for community tanks. However, they can become shy and skittish if kept in isolation or if the tank lacks sufficient hiding spots and cover.

5.2 Tank Mate Compatibility

Due to their peaceful nature, Glass Bloodfin Tetras are highly compatible with a wide range of other small, non-aggressive species. When choosing tank mates, it’s important to select species that have similar water requirements and temperaments to avoid stress or aggression.

Some ideal tank mates for Glass Bloodfin Tetras include:

• Other Tetras: Species such as Neon Tetras, Cardinal Tetras, and Ember Tetras are great companions for Glass Bloodfin Tetras, as they share similar water parameters and peaceful behavior.
• Corydoras Catfish: Corydoras are bottom-dwelling, peaceful fish that won’t compete with Glass Bloodfin Tetras for space or food. They help keep the substrate clean and add diversity to the tank.
• Dwarf Gouramis: Dwarf Gouramis are slow-moving and peaceful, making them a good match for Glass Bloodfin Tetras in a community tank.
• Small Rasboras: Harlequin Rasboras and other small, peaceful Rasboras can coexist harmoniously with Glass Bloodfin Tetras.

5.3 Tank Mates to Avoid

While Glass Bloodfin Tetras are generally peaceful and compatible with many species, there are certain fish that should be avoided due to their aggressive or territorial nature. Avoid housing them with large, predatory fish that may view the tetras as prey or fish that are known for fin-nipping.

Some tank mates to avoid include:

• Large Cichlids: Cichlids such as Oscars or Jack Dempseys may harass or eat smaller fish like Glass Bloodfin Tetras.
• Fin-nipping species: Fish like Tiger Barbs or certain species of Danios may nip at the fins of Glass Bloodfin Tetras, causing stress and injury.

By selecting peaceful tank mates with similar water requirements, you can create a harmonious community tank that allows your Glass Bloodfin Tetras to thrive.

6. Health and Common Issues

6.1 Common Health Problems

Glass Bloodfin Tetras are generally hardy fish, but like all aquarium species, they can be susceptible to certain health problems if their environment is not properly maintained. Some common health issues include:

• Ich (White Spot Disease): Ich is a parasitic infection that causes white spots to appear on the fish’s body and fins. It is often triggered by stress or poor water quality and can be fatal if not treated promptly.
• Fin Rot: Fin rot is a bacterial infection that causes the fins to become frayed or discolored. It is usually caused by injury, poor water conditions, or stress.
• Internal Parasites: Glass Bloodfin Tetras may occasionally suffer from internal parasites, leading to weight loss, lethargy, and poor appetite.

6.2 Preventing Disease

To prevent disease and ensure the long-term health of your Glass Bloodfin Tetras, it’s important to maintain excellent water quality, reduce stress, and provide a balanced diet. Here are some tips for disease prevention:

• Regular Water Changes: Perform weekly water changes of 20-25% to keep the water clean and free from harmful toxins.
• Monitor Water Parameters: Regularly test the water for ammonia, nitrite, nitrate, pH, and temperature to ensure stable conditions.
• Feed a Varied Diet: A varied diet rich in vitamins and nutrients will help boost the fish’s immune system and promote overall health.
• Quarantine New Fish: Always quarantine new fish for at least two weeks before introducing them to your main tank to prevent the spread of disease.

If you notice any signs of illness, such as loss of appetite, unusual behavior, or visible symptoms like white spots or fin damage, act quickly by isolating the affected fish and treating them with appropriate medications.

7. Breeding Glass Bloodfin Tetras

7.1 Breeding Behavior

Breeding Glass Bloodfin Tetras in captivity can be a rewarding experience, as they are relatively easy to breed with the right conditions. These tetras are egg scatterers, meaning they will release their eggs and sperm into the water column, and fertilization occurs externally.

To encourage breeding, it’s essential to create a separate breeding tank with optimal conditions, including soft, slightly acidic water and plenty of fine-leaved plants for the eggs to stick to.

7.2 Setting Up a Breeding Tank

A small breeding tank of about 10-20 gallons is suitable for spawning Glass Bloodfin Tetras. The water in the breeding tank should be soft and slightly acidic, with a temperature between 78°F and 82°F (25°C to 28°C) to encourage spawning. Use fine-leaved plants like Java moss or spawning mops to provide a surface for the eggs to stick to.

Once spawning has occurred, it’s important to remove the adult fish from the breeding tank to prevent them from eating the eggs. The eggs will hatch within 24-36 hours, and the fry will become free-swimming after a few days. At this stage, you can begin feeding the fry small, nutrient-rich foods like infusoria or baby brine shrimp.

Conclusion

Glass Bloodfin Tetras are beautiful, peaceful, and easy-to-care-for fish that make an excellent addition to any community aquarium. Their translucent bodies, vibrant red tail fins, and active shoaling behavior bring life and elegance to any setup. By providing a well-maintained tank with stable water conditions, a balanced diet, and compatible tank mates, you can ensure that your Glass Bloodfin Tetras thrive and flourish.

Whether you’re a beginner or an experienced aquarist, these small, graceful fish will bring beauty and tranquility to your aquarium for years to come. With proper care and attention, they will reward you with their vibrant colors, peaceful demeanor, and captivating schooling behavior.