Max Size: up to 15 cm

Red Tail Hemiodus Tetra (Hemiodus gracilis) Species Profile & Care Guide

Although the Red Tail Hemiodus Tetras are known as being Semi-Aggressive, this is not the case. People presumably think this is due to their nervous nature, often intimidating smaller, more slow-moving species because of their large size and because they are fast swimmers.

These fish are a relatively peaceful, skittish, shoaling fish that can be quite timid. When put in a single species aquarium, they are best kept in groups of at least ten or more individuals, and should only be kept in well-established aquariums.

In the community tank, they can be kept in a more extensive Amazon biotope set up in small groups with peaceful, similarly-sized fish. They also go well with rainbowfish, Discus, Bala Sharks and Angelfish. It would be best if you did not house them with much smaller species.

Because these Tetras require pristine water quality compared to other fish and are sensitive to poor water conditions, they are not recommended for beginner aquarists. You will be required to do regular partial water changes, and you will need a large tank as these fish do not do well in small aquariums.

The Red Tail Hemiodus Tetra has a strong body that is slightly flattened on the sides with a deeply forked tail. Their body colour is silvery with greenish tones, and they display a black band that starts in the middle of their body and ends at the lower edge of the caudal fin. An intense red strip directly below the black bar on the lower edge of the caudal fin sets the fish off.

Quick Facts
Scientific NameHemiodus gracilis
Other NamesSlender Hemiodus, Red Hemiodus Tetra
OriginsSouth America
Aquarium LevelMiddle - Top
Best kept asGroups 10+
Lifespanup to 8 years
Water Conditions
Water TypeFreshwater
Temperature72 - 80 ℉ (22.2 - 26.7 ℃)
PH5.5 - 7.5
GH4 - 15
Red Tail Hemiodus Tetra
Red Tail Hemiodus Tetra
Red Tail Hemiodus Tetra

Natural Habitat of the Red Tail Hemiodus Tetra

The Red Tail Hemiodus is endemic to Brazil, Guyana and Venezuela in South America. They inhabit clear, clean, fast-flowing and highly oxygenated waters in streams, rivers, floodplains and lakes usually with some dense vegetation such as twisted roots and driftwood branches and sandy substrate.

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The Red Tail Hemiodus is Unfussy and will accept most dried food such as high-quality granules and flakes along with live and frozen fare such as bloodworms, mosquito larvae, brine shrimp and blackworms.

Try to make sure it receives some vegetable material in their diet, as it is said they feed quite heavily on plant matter in nature.

Sexing the Red Tail Hemiodus Tetra

Unfortunately, it is practically impossible to sex the Red Tail Hemiodus Tetra. It is believed that mature females are likely to be more rounder-bellied than males.

Breeding the Red Tail Hemiodus Tetra

Red Tail Hemiodus Tetras have not been successfully bred in the home aquarium environment, and there are no records or information about their breeding habits other than the fact that they are egg scatterers.

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Date Added: 09/11/2020 - Updated: 09/11/2020 16:17:14