Category: Tetra
Common Names: Head and Tail Light Tetra
Scientific Name: Hemigrammus ocellifer
Family: Characidae
Minimum Tank Size: 10 Gallons
Care Level: Easy
Temperament: Peaceful
Max Size: 2 Inches
Temperature: 72-80 F
pH: 6.0-8.0
Tank Level: Middle to Top
Colors: White, Yellow, Red
Diet: Omnivore
Breeding: Moderate

Head and Tail Light Tetra: Species Overview
It may be a mouthful, but the head and tail light tetra is a friendly schooling fish with a car taillight appearance, thanks to two dots spaced apart on its body.
These fish are popular for their sparkling metallic bodies and the life they bring to the tank due to their schooling ways.
Head and tail light tetras come from warm water in South America, so they require specific tank conditions to stay healthy. But they’re an easy fish to care for, making them a good fit for beginner fish keepers.
By the time you finish this article, you’ll understand the must-knows of caring for these fish.
Distinguishing Features
Some people mistake the head and tail light tetra for the red eye tetra, given that these fish also have a rim of red around their upper eye.
But unlike red eye tetras, the head and tail variety have two copper-colored spots on their body. One spot sits at the base of their tail and the other behind their head.
A black spot also sits in the spot of these copper-colored iridescent circles, making these fish even more unique.
Scientists believe that head and tail light tetras developed these spots as an evolutionary way to deceive predators into determining where the fish’s actual eyes sit (and, thus, the place where it’s easiest to kill the fish).
Some of these tetras have a narrow black line that runs from the spot by their tail to halfway up the side of the body.
Regardless, all head and tail light tetra fish have silver, partially translucent bodies. Their bodies have an iridescent sheen, especially under the proper lighting.
The head and tail light tetra’s fins also have a primarily see-through appearance. Furthermore, these fish have a classic tetra shape with oval bodies.
Origins
As is the case for so many tetras, the head and tail light tetra are originally from freshwater water in South America. It calls the Amazon River home, along with the Orinoco river basin.
As a result, you can find the head and tail light tetra in many countries, including Argentina, Peru, Guyana, French Guiana, Suriname, and Brazil.
These fish thrive in slow-moving streams. They enjoy clear water with lots of vegetation, but they’re resilient in the cloudy water that’s common in the Amazon, especially during the rainy season.
Head and tail light tetras live in areas with substrate rich in a thick mixture of sand, muddy, decaying plants, and stones.
These fish enjoy areas with thick vegetation for hiding, with amazon sword plants and water hyacinth being some of the plants you can find them near.
Size
Head and tail light tetras grow up to two inches long as adults, making them small to medium-sized tropical fish.
Females have a more robust, rounder structure than males, who have a more slender appearance.
Lifespan
Like many tetras, head and tail light tetras have an average lifespan of three to five years.
You can increase the chances of your fish living to the longer end of this spectrum by providing them with ideal water and tank parameters.
It’s also important that you put these fish in groups of at least six so that they can maintain optimal emotional well-being.
Genders
One of the easiest ways to differentiate between male and female head and tail light tetras is by assessing their size.
Females have rounder stomachs than males. The difference in their size becomes even more pronounced when they’re growing eggs and on the brink of spawning.
In contrast, male head and tail light tetras have a more slender appearance.
Another gender difference is that males have a more pointed and visible swim bladder. The female’s swim bladder is rounder.
Since head and tail light tetras have semi-translucent bodies, you’ll be able to see their swim bladder when you turn their aquarium light on a high setting.
Temperament
Head and tail light tetras are peaceful fish. They get along well with other fish of a similar size and those that also have non-aggressive personalities.
It isn’t common for these tetras to become aggressive under most circumstances, although you might notice the males display slightly more feisty personalities when they’re preparing to spawn.
But overall, both male and female tetras are community-friendly fish. They’re also fish that rely on other fish of the same species to socialize and school with.
Tank Parameters
Understanding the proper tank parameters for head and tail light tetras is vital for their happiness and longevity. Below are the items you must prepare before bringing these fish home.
Minimum Tank Size
The minimum tank size you should have for head and tail light tetras is 20 gallons per six fish.
In terms of the tank dimensions, you should aim for a tank no smaller than 24” x 15” x 12”. But the larger the tank you can manage for your fish, the better off they’ll be.
Water Parameters
Without striking the right balance of water parameters, you’re setting up your head and tail light tetra fish for an early trip to the grave. So, be sure to stay within the recommended ranges below.
Temperature
Head and tail light tetras must have a water temperature between 72 and 79 degrees Fahrenheit.
These fish come from warm, tropical regions. So, using an aquarium heater to maintain their water at a consistently warm temperature is vital.
pH
Head and tail light tetras prefer an average neutral pH of 7.0.
But they can also tolerate slightly acidic and alkaline water, given that they can thrive in a pH between 6.0 and 8.0.
Salinity
There’s no need to add salt to a head and tail light tetra tank, given that these are freshwater fish.
But if your fish appear to have ill health or have parasites, adding some aquarium salt can be beneficial for helping to boost their immune systems.
If you decide to add aquarium salt to your tank, follow the instructions on the package to avoid turning their water into a full-blown brackish or saltwater tank.
Tank Setup
With your aquarium water in tip-top shape to receive your new head and tail light tetras, it’s time to prepare the more physical (and fun) aspects of their tank.
Substrate
Head and tail light tetras spend most of their time in the middle of their tank. So, they’re not picky about their substrate.
Nevertheless, we recommend using a fine sand or gravel substrate, preferably dark in color.
Not only will this most closely mimic their natural habitat, but the dark color will help their copper and translucent bodies show up better.
Decorations
Head and tail light tetras care more about having live plants in their tank than decorations. But they’ll still appreciate some floating driftwood and sunken branches or rocks.
These objects will make them feel that they’re in their natural habitat.
Since head and tail light tetras live primarily in the middle portion of the water column, selecting pieces of wood and other decorations that go up high enough into their territory is helpful for giving them places to play and hide.
Plants
Putting plants in your head and tail light tetra aquarium is essential. These fish live in densely vegetated areas in the wild and feel secure knowing they have a place to hide.
Floating plants and those that grow from the bottom to the top of the tank are also ideal for helping to reduce the amount of light in a tank—something that head and tail tetras prefer.
Some excellent plants for head and tail tetras include:
- Red ludwigia
- African water fern
- Duckweed
- Amazon sword
Placing dense groups of plants in your head and tail light tetra tank is essential. But you shouldn’t put so many in the tank that it disrupts your fish’s ability to swim in schools in the open water.
Lighting
An automated aquarium lamp helps let your head and tail light tetras know when it’s day and night, so we recommend installing one.
But you should keep the light on a dim setting, given that these fish live in shadier areas in the wild.
Filtration
A filter and an air pump are both essential items to have in a head and tail light tetra aquarium.
Filters proactively remove debris and toxins in the water that can lead to deadly diseases for your fish. Meanwhile, an air pump ensures the water remains well-oxygenated.
Using an aquarium-approved bag of peat by the filter is an excellent option for mimicking the black water that these tetras have in the wild.
Heating
You’ll need to buy a heater for your aquarium to ensure the water temperature remains warm enough for your head and tail light tetras.
Even economical heaters come with excellent automated regulating features. Nevertheless, keeping a thermometer attached to the side of your aquarium is best so that you can catch a malfunctioning heater before it harms your tetras.
Diet
Because tetras are such a common tropical fish, many commercial flakes and pellets exist for them. These are an excellent base for your head and tail light tetra’s diet, as they contain the omnivorous properties that these fish require.
Nevertheless, it’s best to supplement your tetra’s diet with live, frozen, or dried food.
Some excellent foods to feed your head and tail light tetra include:
- Brine shrimp
- Bloodworms
- Lettuce
- Peas
Allow your head and tail light tetras to eat their hearts out for three minutes two or three times per day. Then, remove the excess food.
Breeding
It isn’t hard to breed head and tail light tetras if you have a separate breeding tank.
You’ll need to set up the breeding tank with live plants and feed the tetras you want to breed with lots of protein once they reach sexual maturity (three or four months old).
Within seven to ten days, you’ll see the females starting to enlarge with as many as 800 to 1,000 eggs.
The spawning process often lasts the duration of a morning. Once it’s complete, move the males and females back to their tank immediately so that they don’t eat their offspring.
You can then expect the baby fry to hatch within one day. Feed the baby fish flake or pellets designed for young tropical fish.
Before long, your juvenile head and tail light tetras will be large enough to place in a tank with other fish.
Common Diseases
It’s possible to prevent many diseases in head and tail light tetras by keeping their tank clean and quarantining new fish before adding them to their tank.
Nevertheless, illness can still arise. Below are some of the most common conditions that these fish suffer from.
Dropsy
Dropsy is an umbrella term for a situation that causes fluid to build up in a head and tail light tetra’s stomach.
It can result from several conditions, such as parasites, bacteria, or liver issues. You’ll need to use different mediations to get to the bottom of its cause.
Ich
Ich is a common parasitic infection. The parasites burrow beneath a head and tail light tetra’s scales, causing them to have white spots and itch.
Increasing the water’s temperature and applying ich medication is the best way to treat this condition.
Fin Rot
Fin rot is an aliment in head and tail light tetras that eats away at the fins due to bacteria or fungus. Signs of fin rot include the fins that stick together and become stringy.
An anti-bacterial or anti-fungus medication is often effective at treating this non-life-threatening condition.
Potential Tank Mates
Head and tail light tetras get along with essentially all community-oriented fish of a similar size.
Furthermore, pairing your tetra’s tank mates with fish that enjoy living at the top or bottom of the tank is ideal, given that they won’t compete for space.
Some excellent tank mate species to consider adding to your head and tail light tetra tank include:
- Barbs
- Danios
- Rasboras
Remember that you’ll need to increase the size of your tank to accommodate extra fish according to the number of gallons the tank mates require.