Hyphessobrycon cyanotaenia 2–2.5 cm | Blue-Tailed Tetra

Overview

Hyphessobrycon cyanotaenia, often sold as the Blue-Tailed Tetra, is a small, eye-catching South American characin that brings movement, colour and natural behaviour to the home aquarium. At just 2–2.5 cm on sale, these young fish will grow into elegant, active shoalers that look their best in a group. Their subtle metallic tones and attractive blue accents make them a superb choice for planted community tanks, especially where a calm, natural display is the goal.

This species is best kept in a proper shoal, where it feels secure and displays more confidently. In the right setup, it is peaceful, hardy and rewarding to keep, making it a great option for aquarists looking for a smaller tetra with a refined look rather than a bold neon pattern. As with all live fish from Tropical Fish Co, your order is backed by our live arrival guarantee and fast UK delivery, so your new fish arrive in the best possible condition.

These tetras suit aquariums with gentle filtration, open swimming space and plenty of planting. They are especially effective in groups of eight or more, where their schooling behaviour becomes much more natural and visually impressive.

Care at a Glance

Origin & Natural Habitat

Hyphessobrycon cyanotaenia is a South American tetra from the characin family, associated with soft, warm freshwater habitats. Like many species in the genus Hyphessobrycon, it is adapted to calm waters with plenty of cover, such as slow-moving tributaries, flooded forest margins and vegetated areas where leaf litter, roots and submerged plants provide shelter.

In nature, fish from this group often live in slightly acidic to neutral water with low to moderate hardness. They are accustomed to dimmer, tannin-stained environments and benefit from a similar aquarium layout. Recreating this with driftwood, dried leaves, fine-leaved plants and subdued lighting helps reduce stress and encourages natural schooling behaviour.

Because they are social fish, they are rarely at their best when kept singly or in too-small numbers. A proper shoal not only improves their confidence but also enhances their colour and activity levels.

Tank Setup & Water Parameters

A planted community aquarium is the ideal home for Blue-Tailed Tetras. A tank of at least 60 litres is recommended for a small shoal, though larger aquariums are always better if you want a fuller group and more stable water conditions. A longer tank is preferable to give them room to school and cruise through the midwater.

Use a gentle filter with a mature biological cycle and avoid strong, turbulent flow. These fish appreciate clean, well-oxygenated water, but they do not enjoy being blasted around the tank. Fine sand or smooth gravel works well, and aquascaping should include open swimming areas alongside dense planting. Floating plants can help soften the light and make the fish feel more secure.

Recommended water values are:

• Temperature: 23–28°C
• pH: 5.5–7.0
• General hardness: Soft to moderately soft water is preferred

Regular maintenance is important. Perform weekly partial water changes, keep nitrate low and avoid sudden changes in temperature or chemistry. Stable conditions are more important than chasing exact numbers. If you are acclimating newly arrived fish, do so carefully and allow them time to settle before feeding heavily.

For best results, keep them in a shoal of at least 6, though 8–12 is even better. Larger groups spread confidence through the shoal and reduce skittish behaviour.

Feeding Guide

Hyphessobrycon cyanotaenia is an omnivore and will accept a wide range of prepared and frozen foods. A varied diet helps maintain colour, condition and long-term health. Offer a quality micro pellet or small flake as the staple, then supplement with frozen or live foods such as daphnia, baby brine shrimp, cyclops and finely chopped bloodworm.

Feed small amounts once or twice daily, only what the fish can consume in a couple of minutes. Overfeeding can quickly affect water quality, especially in smaller aquariums. A mixed diet is ideal, and occasional live foods can encourage natural feeding response and activity.

Because these are small fish, choose appropriately sized foods. Crushed flake, micro granules and tiny frozen items are usually best. A healthy feeding routine should leave them active, rounded but not bloated, and eager to feed without becoming aggressive at the surface.

Tank Mates / Compatibility

Blue-Tailed Tetras are peaceful community fish and do best with other calm species of similar size and temperament. Good tank mates include small rasboras, other peaceful tetras, Corydoras catfish, Otocinclus, small gouramis with gentle temperaments, and dwarf livebearers in suitable water conditions. They also work well in planted community setups with non-aggressive bottom dwellers and similarly sized schooling fish.

Avoid large, boisterous or predatory fish that may intimidate them or view them as food. Fin-nippers should also be avoided, as should very territorial species that occupy the same water layers. Fast, highly active fish can stress them if the tank is too small or sparsely decorated.

As with many small tetras, they are best kept in a species-appropriate shoal. When comfortable, they will spend much of their time in the middle of the aquarium, moving together and creating a lively, natural display.

Why Buy from Tropical Fish Co

At Tropical Fish Co, we take pride in supplying healthy, well-conditioned live fish with careful packing and reliable service. Our fast UK delivery helps reduce transit time, while our live arrival guarantee gives you confidence when ordering online. We understand that live fish are a specialist purchase, so we focus on quality, consistency and customer care from dispatch to delivery.

When you choose us, you benefit from fish selected with care and shipped with attention to welfare. We aim to make it easy to build a thriving aquarium with species that are correctly identified, accurately described and suitable for the home hobbyist. If you are looking for a peaceful tetra that adds subtle colour and elegant schooling behaviour to a planted tank, Hyphessobrycon cyanotaenia is an excellent choice.

Order today and enjoy a beautiful shoaling fish that rewards good husbandry with colour, confidence and constant movement.