Species Profile of the Head and Tail Light Tetra (Beacon Fish)

Hemigrammus ocellifer - Head and Tail Light Tetra

The head and tail light tetra is native to freshwater rivers and streams in South America and is most recognized for its coppery patches that resemble taillights. This tetra species is a tranquil schooling fish that does not require a huge tank. It does, however, require a lot of open swimming space and dim illumination to be happy.

Species Overview

Common Names: Beacon fish, beacon tetra, head and tail light tetra

Scientific Name: Hemigrammus ocellifer

Adult Size: 2 inches

Life Expectancy: 5 years


Family Characidae
Origin Argentina, Brazil, French Guiana, Guyana, Peru, and Suriname
Social Peaceful, schooling fish
15 gallon
Diet Omnivore
Breeding Egglayer
Care Easy
pH 6 to 8
Hardiness 5 to 19 dGH
72 to 79 F (22 to 26 C)

Origin and Distribution

Hemigrammus ocellifer is native to South America, where it may be found in a variety of habitats around the Amazon River, the Orinoco River basin, and the coast of Guyana. It may be found in Argentina, Brazil, French Guiana, Guyana, Peru, and Suriname, and prefers slow-moving rivers and streams. Most wild-caught species are now captive-bred for commercial sale, therefore they are rarely offered in the aquarium trade.

Their scientific name is derived from the Greek words Hemmigrammus, which means "half-line," and ocellifer, which means "eye bearing," referring to the fish's reflecting patches or "eyes" on the head and tail. This species was formerly classified as Tetragonopterus ocellifer before being shifted to the Hemigrammus genus.

Colors and Markings

Adults grow to around two inches in length (5 centimeters). The body of this fish is iridescent silver in color and oval in shape, like many other tetras. The body is compressed when viewed from above, and males are slimmer than females. Similar to the redeye tetra, the top rim of the eye is bordered in vivid red. The body and fins are transparent, and a faint black line runs from the mid-body to a place on the tail fin on certain specimens.

The two coppery colored reflecting dots that mimic car lights are dubbed head and tail light tetras. One is at the head, adjacent to the gill cover, while the other is towards the base of the tail. These reflective patches have a black mark on them. This spotting pattern's inheritance is particularly interesting since it most likely functions as a false "eyespot," imitating the reflected red hue of the retina of the fish's eye.

Hemigrammus ocellifer falsus, has been named as a possible subspecies of this fish. It is more slender and has the “taillight” spot, but lacks the spot behind the gill cover.


Head and tail light tetras behave best in groups of six or more and may be maintained with other calm fish, especially those of the tetra family. Barbs, danios, rasboras, and other gentle tiny to medium-sized fish make excellent companions. Small loaches, catfish, dwarf cichlids, and gouramis are also good choices.

To avoid are fish that are large enough to eat tetras. Also note that head and tail light tetras may nip at the fins of slow-moving, long-finned species such as angelfish and bettas.

Head and Tail Light Tetra Habitat and Care

Set up a biotope aquarium with plants to watch this small tetra sparkle. Shade is provided by floating or tall plants that reach the top of the tank, which is especially beneficial because this fish enjoys shaded areas.

Use river sand or a darker base to complement the muted color scheme. Add some tangled roots and driftwood branches. A couple handfuls of dried leaves (beech or oak leaves work well) would round off the look. Allow the wood and leaves to turn the water a weak tea color. To avoid rotting and fouling the water, remove the old leaves and replace them every few weeks.

To help simulate dark water conditions, place a small net bag packed with aquarium-safe peat in the filter. To finish the optimal tank setup, leave some free swimming room in the centre.

Head and Tail Light Tetra Diet and Feeding

The head and tail light tetra is an omnivorous creature that will consume almost everything except living plants. Combine flake foods with freeze-dried or frozen live foods like brine shrimp, bloodworms, and minute insects. They will also consume fine pelleted food. When training before breeding, only live meals should be utilized.

Gender Differences

When viewed from above, females appear rounder and plumper than males. The male's internal swim bladder is pointed and more apparent than the female's spherical swim bladder. Because this fish is transparent, the swim bladder may be seen by candling it over a bright light.

Breeding the Head and Tail Light Tetra 

This tetra is an egg-layer and is reasonably easy to breed. The breeding couple should be able to lay their eggs on a variety of plants in the tank. Dim lighting is recommended. The water in the aquarium should be soft, with a temperature of 80 degrees Fahrenheit (26 degrees Celsius) and a slightly acidic pH of 6.0 to 6.5.

For a week or two, feed the breeder pair live meals. Bloodworms and brine shrimp are wonderful options, and if live food isn't available, frozen food can be utilized. The female's belly will grow substantially with eggs as spawning time approaches. Spawning usually takes place in the morning, with up to 1,000 eggs deposited throughout the day.

Remove the parents as soon as the eggs are deposited; otherwise, they will eat the eggs and young fry. The eggs will hatch in 24 hours, and the fry will be able to swim freely in two days. Ensure that the illumination remains dim during this time. If the room is brightly lighted, drape the tank to decrease the amount of light. Commercially prepared fry meal, egg yolk, or Infusoria should be fed to the fry. Freshly hatched brine shrimp can also be given to the fry after a few days.

More Pet Fish Species and Further Research

If head and tail light tetras appeal to you, and you are interested in some compatible fish for your aquarium, check out:

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