Glowlight tetra Care Guide: Diet, Tank Mates, Diseases, Breeding & More

Updated: October 29, 2022

The Glowlight Tetra is a beautiful freshwater fish that is perfect for beginner aquarium hobbyists. They are easy to care for, and are very peaceful fish that get along well with other community fish.

Glowlight Tetras are a great addition to any freshwater aquarium, and in this guide we will teach you everything you need to know about Glowlight Tetra care.

Species overview

The Glowlight Tetra (Hemigrammus erythrozonus) is a freshwater fish that is native to the rivers of South America, specifically in the countries of Brazil, Peru, and Columbia.

They prefer to live in areas of slow-moving water with a lot of vegetation. This provides them with plenty of places to hide and forage for food.

Glowlight Tetras are a very peaceful fish that do well in community tanks. They can be kept with a wide variety of other fish, as long as they are of a similar size.

The main draw of the Glowlight Tetra is its bright red coloration. This makes it a popular choice for aquariums, especially those with a black background which really makes the fish pop.


Glowlight tetra

The first thing you’ll notice about this species is their coloration. As the name implies, these fish have a very noticeable glow to them. This color can range from a pale yellow to an orange tint.

The body of the fish is very streamlined with a long and thin shape. The dorsal fin is short and starts about two-thirds of the way back on the body. The anal fin is a bit longer and starts closer to the middle. Both of these fins are relatively tall and thin.

The caudal fin is forked and roughly the same size as the dorsal and anal fins. The pectoral fins are very small in comparison to the other fins and start close to the head of the fish.

One thing that’s worth noting is that the female Glowlight Tetras are usually a bit larger than the males. The males also have a more pointed dorsal fin.


The average lifespan of a Glowlight Tetra is 5 to 8 years. However, there have been reports of these fish living up to 10 years in captivity.

As with any fish, their lifespan will be greatly impacted by the quality of care they receive. Things like water quality, diet, and stress can all shorten their life expectancy.


Most Glowlight tetras only grow to be about 2.5 inches in length. However, there are some reports of them reaching up to 3 inches in the wild. Either way, they are a relatively small fish that doesn’t need a lot of space to swim around.


Tank Size

The minimum recommended tank size for glowlight tetras is 10 gallons. If you’re looking for a small freshwater fish that can fit in an average-sized tank, this is a good option.

Glowlight tetras are a schooling fish so you’ll want to keep them in groups of at least 5 or 6 fish. If you can provide more space, we recommend it, as a larger school will be happier and healthier.

Water Parameters

The preferred water parameters for glowlight tetras are pretty typical for a freshwater fish. They come from slow-moving rivers and streams in South America.

The water is typically on the warm side with a neutral to slightly acidic pH. There’s also plenty of vegetation for the fish to hide in and plenty of places to find food.

Here are a few water parameters to help you set up a glowlight tetra tank.

  • Water temperature: 70 to 80 degrees Fahrenheit
  • pH levels: 6.0 to 7.5
  • Water hardness: 2 to 8 dGH
  • Alkalinity Levels: 4-8 dKH

What To Put In Their Tank

The interior of their tank is very important to them. You want to make sure that it’s set up in a way that’s comfortable for them and won’t stress them out.

Glowlight tetras are a schooling fish, which means they like to be around other fish of their own kind. This is why we recommend a tank that’s at least 20 gallons.

The substrate in their tank can be anything you want. They’re not fussy when it comes to that sort of thing.

As for plants, they’re not going to eat them so you can go with whatever you want. We recommend something that can provide some cover for them like Hornwort or Java Fern.

These fish also like a bit of driftwood in their tank. It gives them something to swim around and provides a hiding spot when they need it.

One last thing to note is that these fish are very sensitive to changes in their environment. We recommend slowly acclimating them to any new tank conditions.

Common Diseases

The most common disease that affects glowlight tetras is, you guessed it, ich. This is a very common freshwater disease that can be caused by a number of different things (poor water quality, stress, etc).

The most obvious symptom of ich is the presence of white spots on the body of your fish. These spots will eventually turn red and can cause your fish a lot of discomfort.

If you think your fish might have ich, the best thing you can do is to consult your vet. They will be able to give you a diagnosis and help you come up with a treatment plan.

Of course, the best way to prevent your fish from getting sick in the first place is to maintain a clean and stable habitat. This will help to keep your fish healthy and reduce the risk of disease.

Behavior & Temperament

The Glowlight Tetra is a peaceful community fish that is active and easy to care for. They are a perfect addition to a nano aquarium or a planted tank and make a great addition to a peaceful community.

Glowlight Tetras are social fish and do best in groups of 6 or more. They are schooling fish that like to stay close to their school mates. In the wild they can be found in large schools of 100 or more fish.

The Glowlight Tetra is an active fish that spends most of its time in the middle to top of the aquarium. They are constantly swimming and exploring their surroundings.

Glowlight Tetras are not aggressive fish and get along well with other peaceful community fish.

Tank Mates

Glowlight tetras are peaceful community fish that do well in groups. In the wild, they’re found in large schools numbering in the hundreds.

The good news is that you can recreate this dynamic in your home aquarium. All you need are a few compatible tank mates to get started.

Here are some of the best fish to keep with glowlight tetras:

  • Neon Tetras
  • Cardinal Tetras
  • Black Neon Tetras
  • White Cloud Mountain Minnows
  • Rummy Nose Tetras
  • Ember Tetras
  • Harlequin Rasboras


Glowlight tetras are easy to breed in the home aquarium. They don’t have any special requirements and will readily breed in most community tanks.

The first step is to set up a breeding tank. It should hold at least 10 gallons of water. The water should be soft with a pH between 6.0 and 7.0. You can use an air stone to keep the water well-oxygenated.

Next, add some plants and other hiding places. Glowlight tetras like to lay their eggs in plants. Java moss is a good option.

When ready, add a group of 6 to 8 fish to the tank. It’s best to have more females than males. The ratio should be about 2:1.

The fish will start to pair off and mate. After a few days, you should see the female start to lay eggs. She’ll lay them on the plants or on the glass.

Once the eggs have been laid, remove the adults from the tank. The eggs will hatch in about 24 hours.

The fry will be very small and vulnerable. They’ll need to be fed live foods such as microworms or brine shrimp. You can also give them crushed-up flake food.

As they grow, you can start to add them to your main tank.


As you can see, there are many benefits to owning Glowlight tetras. They are a beautiful addition to any freshwater tank and are very easy to care for. They are also a peaceful fish that gets along well with other community fish.

The only downside to owning these fish is that they are prone to fin nipping. However, this can be prevented by keeping them in a well-planted tank with plenty of hiding spots.

Overall, we think Glowlight tetras are a great choice for any freshwater tank and we hope you will consider them for your own aquarium!