Glass Bloodfin Tetra – Prionobrama filigera

Among the more delicate and underrated characins, the Glass Bloodfin Tetra (Prionobrama filigera) stands out as a shimmering, semi-transparent jewel. Its graceful body, subtle coloration and active, schooling behaviour make it an ideal resident for peaceful community aquariums. In this article we will explore its natural origin, everyday care, ideal aquarium setup and compatibility with other species, so that you can confidently keep this fascinating fish at home. At MB Store you will also find the aquariums and technical equipment needed to create a stable, comfortable environment for Glass Bloodfin Tetras and their tank mates.

Natural habitat and appearance of Glass Bloodfin Tetra

The Glass Bloodfin Tetra, Prionobrama filigera, comes from slow-flowing rivers and flooded forest areas of South America, mainly in the Amazon and surrounding basins. In nature it inhabits calm, often tannin-rich waters with dense shoreline vegetation and plenty of open swimming space. The water there is usually soft to moderately hard, slightly acidic to neutral, and often coloured light brown by decaying leaves and branches.

The common name “Glass Bloodfin” refers to the almost transparent, glass-like body of the fish combined with the reddish hue in the fins. Adult specimens reach about 5–6 cm in length, making them a typical small tetra perfect for medium-sized community aquariums. The body is elongated and slender, with a slightly arched back and a pointed snout. In clear, well-lit water you can admire the shimmering reflections of light on its scales and faint silver or golden highlights running along the lateral line.

The fins are relatively large compared with the body, especially the anal fin, which extends along much of the belly. The caudal fin often shows a delicate reddening toward the edges, while the other fins may display subtle red or orange tints depending on lighting, diet and mood. This species looks particularly stunning in planted aquariums with dark substrate, where the contrast emphasises its delicate shape and near-transparency. A healthy Glass Bloodfin Tetra will appear active, with fins fully extended and colours slightly more vivid during social interaction or courtship.

In the wild, these tetras occur in shoals that may number hundreds of individuals. This schooling lifestyle is both a defence mechanism against predators and an efficient way to search large areas for small invertebrates and plant material. Recreating at least a modest version of this group structure is essential in the aquarium; a small group of three or four fish will often appear shy and stressed, whereas a group of ten or more will display natural, confident behaviour and constant, yet peaceful, activity in the mid-water column.

Recommended aquarium setup

To keep Glass Bloodfin Tetras successfully, the aquarium should combine open swimming space with areas of cover. A tank length of at least 80–90 cm is recommended for a group of 10–12 specimens, which typically translates to a minimum capacity of around 100–120 litres. Longer tanks are preferred over tall, narrow ones, as these fish appreciate horizontal space for schooling and quick directional changes. At MB Store you will find aquariums in various sizes and shapes, as well as suitable cabinets and covers to create both aesthetic and practical setups.

Water parameters should reflect the species’ natural conditions. Aim for a temperature between 23–27 °C, pH in the range of 6.0–7.5 and general hardness (GH) from 2 to about 12 dGH. Stability is more important than chasing exact numbers; Glass Bloodfin Tetras adapt well as long as sudden swings are avoided. Using a reliable heater with a thermostat and a precise thermometer is highly advisable. MB Store offers heaters, test kits and accessories that help maintain these parameters within a safe, comfortable range for your fish.

A gentle to moderate filtration is necessary to ensure good oxygenation and clarity without creating a strong current that would exhaust the fish. Internal or external filters with adjustable flow are ideal. Choose a model that allows you to direct water movement along the back of the tank, leaving calmer mid and foreground areas. Biological filtration media with large surface area will support colonies of beneficial bacteria that convert harmful ammonia and nitrite into relatively less toxic nitrate. Regular filter maintenance and partial water changes (20–30% weekly) are crucial to long-term health.

Substrate choice plays a large role in the visual impact of these semi-transparent fish. Dark sand or fine gravel makes their light body and subtle red fins more visible. Additionally, a dark base tends to make fish feel more secure, reducing stress and enhancing colouration. You can enrich the setup with driftwood, root structures and leaf litter to simulate their natural biotope; catappa leaves or oak leaves release tannins that slightly tint the water and provide additional shelter for shy individuals. MB Store stocks a variety of substrates, decorative woods and botanicals that are safe for aquarium use and support a more natural environment.

Lighting should be moderate, not overly bright, to prevent the transparent body from appearing washed out. Floating plants such as Salvinia or Amazon frogbit can help diffuse light and offer dappled shade, further calming the fish. In planted aquariums, LED lighting with adjustable intensity is very useful, allowing you to tune the brightness according to plant species and the comfort level of the tetras. Glass Bloodfin Tetras look particularly appealing under slightly warm-white light that accentuates their faint reds and the green tones of surrounding plants.

Planting, decorations and aquascaping ideas

Although Glass Bloodfin Tetras do not have specific plant requirements, they show their best behaviour and colours in a well-planted tank with a combination of dense vegetation and open water. Fast-growing stem plants such as Hygrophila, Limnophila or Rotala can form lush background thickets, offering a sense of security and places to retreat. Foreground plants like small crypts or carpeting species add texture near the substrate and help create a more natural visual transition between open areas and denser corners.

Floating plants, apart from moderating the light, provide interesting visual layers and can help reduce stress in sensitive fish. Their trailing roots serve as hiding spots for fry if breeding occurs. In the middle of the tank, consider using pieces of driftwood or branchy root structures to create vertical elements that break the line of sight without blocking swimming routes. The contrast between the dark wood and the delicate, translucent bodies of Glass Bloodfin Tetras creates a very appealing composition.

When aquascaping for this species, try to maintain a large, unobstructed zone in the central part of the aquarium where the group can school freely. Place taller plants and larger decorations along the back and sides, leaving enough free space for dynamic movement. This gives you the opportunity to observe natural interactions such as subtle dominance displays, coordinated changes of direction and short chases that rarely escalate into aggression. By emphasising perspective and depth in your layout, you will make the tank appear larger and more immersive both for you and for its inhabitants.

Subtle use of stones can complement wood and plants, but avoid sharp, rough pieces that could damage the fins or bodies of these delicate fish. Rounded river stones or smooth rocks are safer choices. It is also wise to check whether any rocks significantly alter water hardness or pH; some calcareous stones can raise these parameters, which may not be desirable if you aim to keep the water on the softer, slightly acidic side. Testing water before and after introducing large decorative elements helps ensure that your chosen materials do not overshoot your target parameters.

MB Store offers a broad range of decorative substrates, natural stones, driftwood and aquarium-safe ornaments, enabling aquarists to design anything from a near-biotope setup to a more stylised planted display tank. By combining these materials with appropriate lighting and background colours, you can highlight the glassy bodies and lively movement of your Glass Bloodfin Tetras, transforming your aquarium into a calm, living centrepiece in your home or office.

Behaviour, social structure and tank mates

Glass Bloodfin Tetras are peaceful, active schooling fish that prefer to stay in the middle and upper layers of the water column. They are most comfortable in groups of at least eight to ten individuals, and larger schools are even better. When kept in too small a group, they may become timid, spending most of their time hiding among plants and showing duller colours. In a proper school, they exhibit attractive coordinated swimming, playful chases and ongoing interactions that give the aquarium a lively, yet harmonious, character.

Their temperament is generally gentle, making them well suited to community aquariums. They rarely nip fins and usually ignore other species as long as they are not excessively cramped. However, because of their delicate size and transparent bodies, they should not be kept with large or aggressive fish that could see them as prey or competitors. Avoid combining them with big cichlids, very territorial barb species or overly boisterous catfish that might disturb their calm behaviour.

Ideal tank mates include other small tetras, rasboras, peaceful dwarf cichlids such as Apistogramma, and various small Corydoras catfish. Many small livebearers, such as guppies or Endler’s livebearers, can also coexist successfully, provided that water parameters overlap and the aquarium is spacious enough. When mixing species, pay attention to differences in temperature preferences, hardness and pH, aiming for a range acceptable to all residents. Observation after introducing new fish is essential to ensure that no subtle harassment or competitive stress occurs.

Despite their calm nature, male Glass Bloodfin Tetras may show mild territorial behaviour during feeding or courtship, especially in densely stocked tanks. These displays usually involve short, non-damaging chases and fin flaring, with no serious injury. A well-structured environment with plenty of plants and hiding spots helps to disperse tension and allows weaker individuals to retreat. Maintaining a balanced male-to-female ratio and an adequate group size spreads any social pressure more evenly across the school.

Because they are sensitive to abrupt changes, these tetras react quickly to water quality issues or sudden shifts in parameters. Signs of stress include clamped fins, lethargy, erratic swimming and retreating constantly into dense vegetation. Regular maintenance, gentle acclimation when introducing new fish or performing large water changes, and avoiding overcrowding are key management practices. With appropriate care, Glass Bloodfin Tetras reward the aquarist with long-lasting health, natural behaviour and a sense of calm motion in the aquarium.

Feeding and nutritional needs

Glass Bloodfin Tetras are omnivores with a preference for small animal-based foods. In nature they feed on insect larvae, tiny crustaceans and other planktonic organisms, supplemented by plant matter. In the aquarium they readily accept a wide variety of foods, which makes feeding relatively simple, but quality and diversity remain crucial to long-term vitality, colouration and resistance to disease.

A good base diet consists of high-quality flake or micro-pellet food specifically formulated for small tropical fish. Choose products with a high proportion of protein from fish or crustacean sources, added vitamins and stable ingredients. Fine granules that sink slowly are especially suitable, as they allow the fish to feed at their preferred mid-water depth without having to compete aggressively at the surface. MB Store provides a wide selection of premium dry foods developed for small tetras and other community species.

To stimulate natural feeding behaviour and enhance colour, regularly supplement dry foods with frozen or live treats. Daphnia, cyclops, micro bloodworms and Artemia nauplii are ideal options. These foods encourage hunting instincts, promote strong immune systems and often trigger more intense social and courtship displays. When feeding such high-protein items, moderation is important; use them two to three times a week rather than as the sole daily staple to avoid digestive issues and excessive pollution of the water.

Plant-based supplements such as finely crushed spirulina flakes or blanched spinach can also be offered occasionally. While not strictly necessary if using balanced commercial feeds, they introduce additional phytonutrients and fibre, aiding digestion. Observing the behaviour of your Glass Bloodfin Tetras at feeding time is a good indicator of their general condition; healthy specimens quickly gather in the feeding area, showing quick, precise movements and actively competing for food without signs of aggression.

Overfeeding is a common mistake with small, fast fish, as their eagerness may tempt the aquarist to add “just a little more.” Each feeding session should provide only as much as the fish can consume within about two to three minutes. Excess food that sinks to the bottom not only wastes money but also decays, increasing ammonia and nitrate levels and encouraging algae growth. Regular siphoning of debris from the substrate and careful portion control will keep your water parameters stable and your Glass Bloodfin Tetras in good condition.

Breeding Glass Bloodfin Tetra in the home aquarium

Breeding Glass Bloodfin Tetras is achievable for dedicated aquarists who are willing to prepare an appropriate environment and pay attention to detail. As egg-scattering spawners, they do not show parental care and may eat their own eggs or fry if given the opportunity. Because of this, successful breeding often requires a separate spawning tank and careful handling of adults and offspring.

A breeding aquarium of around 30–60 litres is sufficient, equipped with a sponge filter for gentle filtration and a heater maintaining temperature around 26–27 °C. The water should be soft and slightly acidic, with pH between 6.0 and 6.8 and low hardness. Use fine-leaved plants like Java moss, spawning mops or artificial fibre spawning media, which provide surfaces where eggs can adhere and offer hiding places for emerging fry. Gentle lighting helps create a calm atmosphere and may improve spawning success.

Conditioning potential parents is a crucial step. Over one to two weeks, feed the selected male and female (or a small group) with abundant frozen and live foods to encourage maturation of eggs and sperm. Well-conditioned females appear fuller in the belly region, while males may display more intense fin colours and increased courtship behaviour. Introduce the pair or group into the breeding tank in the evening, providing them with privacy and minimal disturbance.

Spawning typically occurs in the early morning hours. The male chases the female through plants or spawning mops, and at the peak of courtship they release eggs and milt simultaneously. The eggs are transparent to slightly yellowish and sink or adhere to surrounding structures. After spawning, it is advisable to remove the adults to prevent them from consuming the eggs. Eggs usually hatch within 24–36 hours, depending on temperature, and the fry become free-swimming a few days later.

At the free-swimming stage, the fry are very small and require microscopic foods. Initial feeding with infusoria or commercially prepared liquid fry foods is recommended, followed gradually by newly hatched Artemia as the fry grow. Frequent small water changes with carefully matched parameters are vital for their survival, as fry are sensitive to pollutants and sudden shifts. With patience and careful management, many fry will reach a size where they can be transferred to the main aquarium or rehomed to other enthusiasts, contributing to the sustainable trade of this charming species.

Health, lifespan and disease prevention

Glass Bloodfin Tetras, when properly cared for, can live for several years, often reaching three to five years of age in home aquariums. Their delicate appearance sometimes gives the impression of fragility, but in stable conditions they are surprisingly robust. Most health problems stem from inadequate water quality, abrupt parameter changes or poor diet, all of which can be prevented through good aquarium management practices.

Common issues affecting this species include external parasites such as white spot disease (Ichthyophthirius multifiliis), fin rot caused by opportunistic bacteria and stress-related conditions that weaken immune response. Early signs of trouble may involve white spots on the body or fins, frayed fin edges, clamped fins, unusual lethargy, or loss of appetite. Observing your fish daily during feeding and at different times of the day enables you to detect subtle changes long before a disease becomes serious.

Preventive care focuses on maintaining clean water and avoiding sudden fluctuations. Perform regular partial water changes, vacuum debris from the substrate and rinse filter media gently in tank water to preserve beneficial bacteria. Testing water for ammonia, nitrite, nitrate, pH and hardness on a regular basis helps you detect trends and correct problems early. MB Store offers reliable test kits, conditioners and filter media that make water management more precise and convenient.

Quarantining new fish before adding them to the main aquarium is another critical preventive measure. A separate, smaller tank used for observation over two to three weeks allows you to identify any hidden diseases and treat them without endangering established inhabitants. During quarantine, watch for abnormal behaviour, visible parasites or unexplained deaths. Only after completing this process should newcomers join your main community of Glass Bloodfin Tetras and tank mates.

In case of disease, accurate identification is essential for effective treatment. Many medications marketed for common freshwater ailments are safe for tetras when used according to instructions, but overdosing can be dangerous to delicate species. Always remove activated carbon from the filter during treatment, as it can absorb the active ingredients, and increase oxygenation by adding an air stone. After completing any treatment, perform partial water changes and reintroduce chemical filtration carefully. With a thoughtful approach, you can minimise losses and quickly restore a healthy, thriving community.

MB Store support for aquarists

Keeping Glass Bloodfin Tetras successfully depends not only on knowledge but also on access to reliable equipment and quality supplies. MB Store provides a comprehensive range of aquariums, from compact models suitable for desktops to larger display tanks ideal for schools of active tetras. Matching stands, covers, LED lighting and fully equipped sets help both beginners and experienced hobbyists build stable, visually appealing systems with ease.

In addition to tanks themselves, MB Store offers heaters, filters, circulation pumps, air pumps, substrates, decorative elements and a wide selection of fish foods and water conditioners. This integrated assortment allows you to design the entire environment for your Glass Bloodfin Tetras in one place, ensuring that all components are compatible and appropriate for delicate community species. If you are planning a new setup or upgrading an existing aquarium, you will find the components needed to support optimal water quality and a safe habitat.

For hobbyists interested in planted aquariums, the store’s selection of plant substrates, fertilisers, CO₂ systems and dedicated lighting makes it easier to maintain dense vegetation that benefits both plants and fish. Healthy plants help stabilise water parameters, reduce nitrates and provide natural shelter and spawning sites for Glass Bloodfin Tetras. By combining strong yet gentle filtration with appropriate lighting and fertilisation, you create a balanced ecosystem that highlights the beauty of both flora and fauna.

MB Store also understands the value of information and support. Alongside products, you can find educational content, expert advice and descriptions of species that guide you through the complexities of aquaristics. Whether you are choosing your first school of Glass Bloodfin Tetras or expanding an existing community tank, the combination of appropriate equipment, quality consumables and knowledge will significantly increase your chances of long-term success and satisfaction in the hobby.

FAQ about Glass Bloodfin Tetra

How large should the aquarium be for a group of Glass Bloodfin Tetras?
For a comfortable group of about 10–12 Glass Bloodfin Tetras you should choose an aquarium of at least 100–120 litres, with a length of 80–90 cm or more. The extended horizontal space allows the school to swim naturally and reduces stress. Larger tanks also offer more stable water parameters and additional room for plants and compatible tank mates, improving the long-term wellbeing of the fish.

What water parameters are best for Glass Bloodfin Tetras?
This species thrives in soft to moderately hard water with a temperature between 23–27 °C, pH around 6.0–7.5 and general hardness of 2–12 dGH. While they are fairly adaptable, stability is more important than perfect numbers, so avoid sudden changes. Regular testing, gradual adjustments and partial water changes help maintain consistent conditions, reducing the risk of stress and diseases associated with parameter swings.

Are Glass Bloodfin Tetras suitable for beginners?
Glass Bloodfin Tetras can be a good choice for attentive beginners who are ready to maintain stable water conditions and keep them in proper groups. They are peaceful, eat most prepared foods and adapt to a range of parameters, but they are sensitive to poor water quality and abrupt changes. With adequate filtration, regular maintenance and careful stocking, even new aquarists can enjoy this species successfully.

What tank mates can I keep with Glass Bloodfin Tetras?
They coexist well with other peaceful, small fish like neon tetras, rasboras, Corydoras catfish and dwarf cichlids. Avoid large, predatory or very aggressive species that might harass or eat them. When selecting companions, ensure overlapping temperature and pH requirements and provide enough space and hiding spots. Observing behaviour during the first weeks after introduction helps confirm that all inhabitants interact calmly and feed without conflict.

How can I tell if my Glass Bloodfin Tetras are stressed?
Stressed individuals may show clamped fins, faded colours, hiding constantly among plants or moving erratically. Rapid gill movement, loss of appetite or isolation from the group are additional warning signs. Check water parameters, temperature and filtration efficiency, and verify that no bullying or overcrowding occurs. Improving environmental conditions, adding more hiding places and maintaining an adequate school size usually help restore normal, active behaviour.