Tetra refers to many common freshwater fishes belonging commonly to the family Characidae. They are found in Africa, South and Central America. There are more than 150 species of Tetras. Tetras are very popular among fishkeepers of all experience levels. Species such as Red Eye Tetras, Black Skirt Tetras, Neon Tetras, and Lemon Tetras are very common choices for beginners.

Tetras are schooling fish. This means they like to stick together in groups and swim in the same direction. To manage and care for Tetras properly, it is important to know how many Tetras should be put in a single tank. In this article, let us find out how many Tetras can be grown together in a 5-gallon tank. If you are also interested in maintaining Guppies in your aquarium, check out our article on how many Guppies can be put in a 10-gallon tank here.

How Many Tetras Fit In A 5 Gallon Tank?

Ideally, a school of Tetras contains about 6 fish. While they are generally peaceful, Tetras can get agitated if their numbers are too few. But a simple 5-gallon tank may not be able to accommodate 6 Tetras and they will become starved for space. This is why you should know how many Tetras can fit in your tank.

For a beginner, a 5-gallon tank should not contain more than 3 to 4 Tetras. If you cram too many Tetras together they will start competing for food and other resources. A 5-gallon tank isn’t the best option for maintaining Tetras. But with plenty of swimming space, vegetation, and proper care it is achievable.

How To Calculate The Number Of Tetras For A Fish Tank?

For calculating the number of Tetras that can fit in a fish tank, we need to know their size first. The size of Tetras varies from species to species. Some species like Black Tetras can grow up to 3 inches in length. Others like Cardinal Tetras or Neon Tetras grow to about 1.5 inches only.

The general rule to follow when calculating the number of small fish for a tank is to have at least 1 gallon of water per inch of fish. This means it is hard to keep bigger Tetra species in a 5-gallon tank. For this reason, we will only consider Tetras that are limited to 2 inches in size, such as Cardinal Tetras, Neon Tetras, Penguin Tetras, Lemon Tetras, and Ember Tetras.

For these species, you can fit approximately 3 Tetras in a 5-gallon tank. If you are an expert, you can take that number a little higher especially for smaller fishes like Penguin Tetras, which grow to about 1.2 inches in length. In these cases, you can push the number of Tetras in the 5-gallon tank to 4 or 5. Anything above this becomes very hard to maintain and should generally be avoided.

What Will Happen If You Add Too Many Tetras?

Putting too many Tetras in a compact space can pose a danger to their well-being. Limited swimming space can lead to overcrowding and agitation, which can cause injuries to the fish. On top of that, smaller tanks with lots of fish are also bound to get polluted very quickly. The Tetras will also end up competing with each other for food, air, and other resources. All this can make your Tetras very stressed and scared.

This is why it is recommended to keep Tetras in at least a 9 to 10-gallon tank. This allows you to keep a healthy amount of schooling Tetras in the tank to keep them from getting lonely and depressed. It also alleviates problems stemming from a lack of space. A 10-gallon tank can easily fit an ideal amount of 5 to 6 Tetras without any problems. If you change your mind about the tank size, you might be interested in this article about how many Neon Tetras can fit in a 10-gallon tank.

Equipment You Might Need For Your 5 Gallon Tank

While it is relatively harder to take care of Tetras in a 5-gallon tank, there are some things you can do to make their stay more peaceful and relaxed. Here is a list of all the equipment you can consider for your 5-gallon tank:

5 Gallon Fish Tank

Obviously, the most important thing is to buy a nice tank for your Tetras. They will live in the tank for their entire lives, so you should choose the tank carefully. You should also clean the tank and cycle it with dechlorinated water before putting your fish in.

The Marineland 5 Gallon Starter Kit is a good and affordable tank for beginners.

Aquarium Heater

Once you’ve decided on the tank, you’d also need the temperature in an appropriate range for the Tetras. If your fish get too cold they will go into shock, leading to either permanent weakness or death. For this reason, you should invest in a reliable heater for your 5-gallon tank. A good rule of thumb for choosing heater wattage is to have at least 5 Watts per gallon of water. However, always make sure to try and test the heater before putting the fish in, and to frequently check the water temperature. You should also change the heater regularly.

You can check out this Hygger 50W Mini Aquarium Heater with an inbuilt thermometer for your tank.

Water Filter

The next piece of equipment you’ll need to get for your tank is a water filter. Filters remove excess food and waste products from the tank to keep your Tetras healthy.

You can refer to this Aquaclear Filter for your 5-gallon tank.

Plants and Decorations

Tetras prefer natural vegetation and planted tanks as it gives them plenty of hiding spots. You should add a proper substrate to the tank to support plant growth. You can also include small rocks and pebbles as decorations. However, try not to overcrowd the tank too much and make sure the Tetras still get plenty of space to swim around.

The ADA Aqua Soil Amazonia is a good choice for your 5-gallon tank.

Aquarium Lighting

Lastly, you’ll need to set up proper lighting for your aquarium. It is important for the health of both – the Tetras as well as any vegetation growing in the tank. Tetras prefer dimly lit environments, so a low wattage fluorescent light should do. If the tank is well planted, you might need to up the wattage a little. However, don’t go for lights that will heat up the water in the tank. Also, keep the lights on for only 12 to 14 hours a day and not more.

Tank Conditions In 5 Gallon Tank For Tetras

The exact tank requirements for your Tetras depend on which species they belong to, but here is a rough idea of what to expect.

Tetras are often found in soft, acidic environments in the wild. But in captivity, they are generally raised in water with a slightly higher pH and alkalinity. For most Tetra species you should try and maintain a pH of 5.5 to 7. The alkalinity should be between 50 to 140 ppm for a hardness of 2 to 10° dH. The temperature should be kept in the 75° to 80° F range.

You should also clean the tank water regularly apart from filtration. Try and change the water gradually, however, as cleaning it too frequently can make the Tetras ill. The water should be kept free from ammonia and nitrites for proper growth.

Tetras are mostly omnivorous and feed on both plants and small animals. However, you should always give them small pieces of food. The feed can consist of mini pellets like shrimp pellets, high-quality flakes with good protein content, bloodworms, fruit flies, lettuce, shredded cabbage etcetera. Tetras generally need to be fed daily, and juveniles can be fed two to three times a day.

Wrapping Up

Tetras are an amazing family of schooling fish which are very popular choices among hobbyists and fishkeepers. They are peaceful, easy to maintain and feed and perform well as pets. While an ideal tank size for Tetras should be around 10 gallons for housing a school of 5 to 6 fishes, a smaller 5-gallon tank can also work for 3 to 4 fishes of some species. However, more care has to be taken in this case not to overstock the tank. Tetras need proper nutrition, swimming space, and perfectly maintained water conditions. But if you are willing to put in the work, they will surely become beloved pets in your aquarium.