The Glass Bloodfin Tetra is an elegant schooling fish with a translucent body revealing its spine and organs. Hardy and ideal for beginners.
Overview
The Glass Bloodfin Tetra (Prionobrama filigera) is one of the most visually striking members of the Characidae family, captivating aquarists with its almost entirely transparent body. Through its colorless skin, the spine and internal organs are clearly visible, giving this fish a truly unique appearance. A vivid red or orange caudal fin provides a striking contrast against the transparent body.
In the wild, Prionobrama filigera inhabits slow-moving rivers and tributaries of the Amazon Basin in South America, primarily in Brazil, Bolivia, and Argentina. The fish grows to 4-6 cm in length and lives 3-5 years with proper care. This is a highly active species that constantly moves through the middle and upper layers of the aquarium. Glass Bloodfin Tetras should be kept in groups of at least 8-10 individuals — in a school, they feel more confident and display their natural shoaling behavior.
Tank Requirements
A school of Glass Bloodfin Tetras requires an aquarium of at least 80 liters. Given the high activity level of these fish, it is important to provide ample open swimming space in the central and upper areas of the tank. Live plants such as Vallisneria, Cryptocoryne, and Java moss can be arranged along the perimeter to create shelter and shaded areas, while leaving an open zone for the school to swim freely.
Optimal water parameters: temperature 22-26 °C, pH 6.0-7.5, hardness GH 5-15. These fish prefer clean, well-oxygenated water with moderate flow. An external canister filter with adjustable flow is recommended. A dark substrate works best — the transparent bodies of these fish look especially impressive against a darker background. Subdued lighting with floating plants on the surface will help the fish feel comfortable.
Feeding and Diet
Prionobrama filigera is an omnivorous fish with an excellent appetite. In the wild, it feeds on small invertebrates, insect larvae, and plant matter. In the aquarium, it readily accepts virtually any appropriately sized food.
A staple diet of high-quality flakes or micro-pellets for tropical fish works well. To maintain health and vibrant coloration of the caudal fin, supplement the diet regularly with live or frozen foods: daphnia, brine shrimp, cyclops, and small bloodworms. Spirulina-based plant supplements are also beneficial.
Feed 2-3 times a day in small portions that the fish consume within 2-3 minutes. Glass Bloodfin Tetras primarily feed in the mid-water column, so slow-sinking foods are the best choice.
Care and Maintenance
The Glass Bloodfin Tetra is one of the hardiest characins, making it an excellent choice for beginning aquarists. However, like all fish, it requires stable conditions to thrive.
Perform weekly water changes of 20-25 %, combining them with gravel vacuuming. Monitor water parameters with test kits — Glass Bloodfin Tetras are sensitive to elevated ammonia and nitrite levels. The aquarium must have a secure lid or cover glass: these fish are excellent jumpers and can easily leap out of the water when startled.
Keep an eye on the fish's condition — thanks to their transparent bodies, many diseases can be detected early by observing changes in the internal organs. A healthy Glass Bloodfin Tetra is active, has a clear transparent body, and displays a bright red-orange tail.
Compatibility
The Glass Bloodfin Tetra is a peaceful fish, perfectly suited for community tanks with other calm species. Excellent tank mates include Neon Tetras, Cardinal Tetras, Flame Tetras, Serpae Tetras, and other small characins. For the bottom level of the tank, Bronze Corydoras and Panda Corydoras make great companions. Among peaceful dwarf cichlids, Bolivian Rams are a suitable choice.
Keep Glass Bloodfin Tetras in groups of at least 8 — in smaller numbers, the fish become timid and spend most of their time hiding. Avoid housing them with large or aggressive species that might view these miniature tetras as prey.
Breeding
Breeding Prionobrama filigera at home is a moderately challenging task, achievable for aquarists with basic experience. These fish are egg scatterers and show no parental care.
Prepare a separate breeding tank of 20-30 liters with a water level of about 15-20 cm. Place fine-leaved plants (Java moss, Cabomba) or a spawning grid on the bottom to protect the eggs. The water in the breeding tank should be soft (GH 4-8), slightly acidic (pH 6.0-6.5), with a temperature of 26-28 °C. Lighting should be dim.
Condition the breeders with generous portions of live foods for a week before spawning. Spawning typically occurs in the morning hours. The female scatters eggs among the plants, and the male fertilizes them immediately. After spawning, the adults must be removed promptly, as they will readily consume their own eggs.
The eggs are transparent and small, with incubation lasting 24-36 hours. The larvae become free-swimming 3-4 days after hatching. First foods include infusoria and micro worms, followed by baby brine shrimp. With good feeding, the fry grow quickly and develop their characteristic body transparency by about two months of age.