Hemigrammus stictus (Blood Tail Tetra)

Overview

The Blood Tail Tetra (Hemigrammus stictus) is a delightful, small freshwater fish belonging to the Characidae family. While not as universally famous as the Neon or Cardinal Tetra, it has garnered a dedicated following among aquarists who appreciate its subtle beauty and dynamic schooling behavior. Its semi-transparent body accented by sharp flashes of black and red makes it a visually interesting addition to community setups.

Distribution and Habitat

This species is native to the freshwater basins of South America, specifically found in the coastal river drainages of Guyana, Suriname, and French Guiana, as well as parts of the Amazon basin. They naturally inhabit slow-moving tributaries, forest streams, and flooded areas. These waters are often tinted brown with tannins from decaying organic matter (blackwater), featuring low light, soft water, and acidic conditions.

Description of Blood Tail Tetra

Body shape:

They possess the classic fusiform, laterally compressed body shape typical of most small characins. This streamlined profile is designed for agile navigation through dense aquatic vegetation.

Color:

The primary body coloration is a shimmering silver to semi-transparent clear hue. A prominent, well-defined black humeral spot (shoulder spot) sits just behind the gill cover.

Barbels:

Like all typical tetras, they do not possess barbels.

Snout:

The snout is relatively short and blunt, featuring a small, terminal mouth adapted for picking micro-invertebrates from the water column.

Eyes:

The eyes are proportionately large compared to the head, often featuring a silver or pale yellowish ring around the dark pupil.

Fins:

The dorsal, anal, pelvic, and pectoral fins are mostly translucent with occasional faint white or silvery tips depending on the lighting and diet.

The Tail:

The defining feature of this fish is its tail base (caudal peduncle), which boasts a brilliant, blood-red patch. The rest of the deeply forked caudal fin remains transparent, making the red coloration pop beautifully against a planted backdrop.

Temper

The Blood Tail Tetra is highly peaceful and timid by nature. It poses no threat to other tank mates and can easily be outcompeted or stressed by larger, boisterous, or aggressive fish.

Sociality

This is an obligate schooling fish. To feel secure, display their best colors, and exhibit natural behaviors, they must be kept in groups of at least 6 to 8 individuals, though larger schools of 12 or more are highly recommended.

Activity

They are highly active mid-water swimmers. Throughout the day, the school will dart continuously through open swimming spaces and weave among plant stems, providing constant, lively movement to the aquarium.

Keeping and Caring for Blood Tail Tetra

Tank size:

A minimum aquarium size of 60 liters (about 15 gallons) is recommended to provide adequate swimming space for a proper school.

Water Parameters:

Maintaining stable water conditions mimicking their natural South American habitat is key to their long-term health.

Temperature

They thrive in tropical temperatures ranging from 23-28°C (73-82°F).

pH

Slightly acidic to neutral water is preferred, with a pH range of 6.0 to 7.5.

Hardness

Soft to moderately hard water is best, ideally between 2 and 12 dGH.

Ammonia, Nitrite, Nitrate

Ammonia and Nitrite must always be at 0 ppm. Nitrates should be kept as low as possible, ideally below 20 ppm, through regular water changes and live plants.

Lighting

Dim to moderate lighting is preferred. Floating plants are an excellent way to diffuse bright aquarium lights and make the tetras feel more secure.

Water flow

A gentle to moderate water flow replicates their natural slow-moving stream habitats without exhausting them.

Decorations and Plants

A dark substrate, ample driftwood, and dense plantings are ideal. Adding dried Indian almond leaves or alder cones will release beneficial tannins, tinting the water and promoting their natural blackwater environment.

Diet

Blood Tail Tetras are omnivorous micro-predators. In the aquarium, they readily accept high-quality crushed flakes and micro-pellets. To ensure optimal health and vibrant coloration, supplement their dry diet with regular feedings of live or frozen foods such as daphnia, baby brine shrimp, and cyclops.

Some Feeding Tips

Feed them small amounts once or twice a day—only what they can consume within two to three minutes. Because of their small mouths, ensure all foods are appropriately sized.

Breeding

Breeding is possible but requires a dedicated setup. They are egg-scatterers that provide no parental care. A separate breeding tank should be set up with very soft, acidic water, dim lighting, and fine-leaved plants (like Java Moss) or a spawning mop. Condition the adults with high-quality live foods. Once eggs are laid and fertilized, the parents will cannibalize them if given the chance, so they must be removed immediately. The eggs hatch in about 24-36 hours, and free-swimming fry will need infusoria before graduating to baby brine shrimp.

Conclusion

The Blood Tail Tetra is a charming and robust little fish that brings a wonderful dynamic to peaceful community aquariums. With their easy-going nature, striking red tail base, and active schooling behavior, they are a fantastic choice for both novice and experienced aquarists looking to populate a well-planted, naturalistic setup.