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How Many Tetras in a 5 Gallon Tank?

How Many Tetras in a 5 Gallon Tank?

If you are an avid fish lover or pet keeper, then you must have heard of, and most likely have come across the tetra fish. Tetra is just the general name of fishes that belong to this species.

How Many Tetras in a 5 Gallon Tank? Tetras are Shoaling fish and that why you should keep them in a group of atleast 5-6. I will recommed you to go with a 10 gallon tank though!

Some of the common tetra fishes and their scientific names are:

  • Cardinal Tetra( Paracheirodon axelrodi)
  • Neon Tetra (Paracheirodon innesi)
  • Rosy Tetra (Hyphessobrycon rosaceus)
  • Green Neon Tetra (Paracheirodon simulans)
  • Ember Tetra (Hyphessobrycon amandae)
  • Diamond Tetra (Moemkhausia pitteri)

Their vibrantly attractive colors and the fact that they are relatively easy to maintain makes them one of the most popular choices for household aquaria.  For a household aquarium, the popularly bred species are the neon tetra, the glofish tetra, the lemon tetra (Hyphessobrycon pulchripinnis), and the black skirt tetra (Gymnocorymbus ternetzi)

To answer the question, how many tetras can be kept in a 5-gallon tank?

A 5-gallon tank would certainly not provide the optimum, stress-free environment required for your tetra to thrive, it would stress your tetras and eventually result in their premature death. The best option would be answered in the next section.

They are freshwater fishes native to the tropics of South America, Africa, and Central America. They are omnivorous fishes, feeding on plants and they also enjoy a tasty brine shrimp or blood worm. It is also acceptable to give them synthetic feeds.

Although the majority of them are docile, there have been cases where tetras have been reported to have been aggressive.

How many tetras can be kept in a 5-gallon tank?

The small size of the tetra fish might mislead you into thinking that keeping so many of them in a five-gallon tank is practicable. We would be looking at two main factors that make this a very bad decision to make.

Size. The principle that should be adopted when it comes to keeping small fishes like the tetra is the one inch per gallon rule, this means that one inch of the tetra fish is estimated to occupy one gallon in the tank (keep in mind that this rule is only applicable to small fishes below 3 inches in size) With the average length of most tetra fishes being about 1.5 inches, it is not ideal to keep more than 3 of them in a gallon.

Shoaling fishes.  Shoaling fishes are simply fishes that live in groups which are referred to as schools, for social and safety reasons. A tetra is a good example of fishes that live in ‘schools’. Although they are a relatively peaceful species, they can easily get agitated or scared when they are few in number.

A school of tetra is ideally made up of 6 member tetras. A five-gallon tank allows you to keep only 3 fishes which is less than the ideal number of fishes that makes up a tetra school, this technically means you need a 9-gallon tank for one school.

How many gallons does a tetra need?

As I have said previously, the rule of thumb for small fishes like the tetra is one inch for every gallon. And a tetra school ideally has about 5 members. So to create the best environment for your tetra, you would need a minimum of 10 gallons.

The actual gallon required by your tetra depends on the number of tetras you would want to keep.

It is acceptable to start with 10 gallons for a maximum of 5 tetras; as you do not want to overcrowd your tank and stress your tetras. In addition to this, tetras are very active swimmers that swim in a horizontal fashion.

A ten-gallon tank would provide fair enough swimming space for your tetras. But to give your tetras a better sense of security, it would be better to keep them in groups of about 15 or more in the appropriate tank size (which should be about 15 or 20 gallons)

The size of the gallon shouldn’t be the only factor you should consider when selecting a tank. You should also consider the temperature and ph of your aquarium.

Since the body temperature of tetras depends on the temperature of their immediate environment, it is important to ensure that the water in your gallon is at the optimal temperature for your tetra, this is about 72 to 80 degrees Fahrenheit; any value higher than this increases the metabolic rate of your tetra and stresses them.

Another factor to consider is the ph of your fish tanks, tetras adapt moderately but the optimal ph of your tank should range from 6 to 7. They are likely to be stressed once the ph is above 7.5.

Lighting and shade should also be considered. Tetras like to hide under plants, so it would be beneficial to include plants in your tank. But do this with moderation, as you do not want your tank to be overcrowded.

How many tetra Glofish in a five-gallon tank?

The Glofish is not one single species of tetra, it is the general name for a diverse group of tetras that have been genetically modified to glow, especially under a fluorescent light. So they are not a natural tetra species; they are basically created in the lab.

They are very colorful and are genetically created in a wide range of colors like yellow, pink, blue, bright red, purple and green. The most popular types of Glofish kept as pets are the Zebra Danio and the White skirt tetra.

This brings us back to the question: how many tetra Glofish should be kept in a five-gallon tank?

The tetra Glofish possesses the same attributes as the natural tetra, which also includes living together in ‘schools’, so it is advisable to keep about 5 of them together.

This means that you require a tank that is at least 10 gallons in size for you to be able to create an optimum environment that would allow your Glofish to thrive without any stress.

If they are few in number, they might become lonely.  Some Glofish tetras have been noticed to become aggressive once they are not in schools.

Cardinal Tetra

How many neon tetras in a gallon?

The Neon tetra, like other tetra species,s is an extremely attractive fish.

Their opalescent bodies, vibrantly colored stripe that run along the length of their bodies Their iridescent stripes makes them glow in your tank. Contrary to the glofish, their opalescence is natural. They are arguably the most popular fishes seen in household aquaria.

Technically, you should keep about two neon fishes per gallon of water but it is completely necessary that you keep them in groups of at least five as they thrive better in groups. If they are alone, they attempt to school with other small fishes that look similar to them.

Their color becomes less vivid once tank quality is poor or when they are stressed. Note that the neon tetra might also appear less ‘shiny’ when it is resting in order to prevent it from being eaten as prey. Even though they are very peaceful, they are very energetic and active, so they require maximum swimming space.

The one inch per gallon rule is also applicable to them, and since they grow to 1.5 inches on an average. Depending on the number of neon tetras you would keep in your tank, the minimum gallon size for one tetra school should be 10 gallons.

In order to create a simulation of their natural habitat, you can include a few shaded plants in your tanks as neon tetras enjoy hiding under shaded plants.

Cleaning Crew for Tetra Tank

Your tank would require a couple of bottom feeders that might act as the cleaning crew, because if organic particulate, algae, and debris are allowed to remain in your tanks, the degradation of this debris and other food particles could result in the production of harmful toxins like ammonia which would reduce the quality of life in your tank and also stress your tetra, making them unhealthy.

Before selecting your cleaning crew, ensure that your tank is not overcrowded so you do not add to the bioload that is already being produced.

Another thing to keep in mind is the size of the cleanup crew, they have to be very small in size so that they are not a source of threat to the fishes in your tank and also so that they do not increase the amount of biodegradable waste produced.

Additionally, you have to include a filter in your tank. A normal sponge filter is effective enough since the bioload generated by Tetra is very little.

Basically,  your clean-up crew feeds on algae only, or as part of their diet

Your cleaning crew has to consist of different species so they can complement each other

Corydoras Catfish: A bottom feeder that is small in size and in addition to feeding on algae, they also feed on meat.

Suckerfish like Plecostomus catfish and Otocinclous. Although the plecostomus catfish is an effective cleaner, this is only before it reaches maturity as it can grow to be four times as big as the tetra.

Nerite snail: in addition to cleaning up very effectively, the nerite snail is also very attractive and would not overpopulate your tank since they do not reproduce in freshwater.

Siamese Algae Eater: this species of fishes are very efficient at cleaning the your fish tank, in addition to being peaceful bottom feeders, they also feed exclusively on diverse algae species.

More: How to Clean Fish Tank Gravel

Crayfish. They are scavengers that can feed on practically anything, from fish food to leaves and even the waste product of your tetra if there is nothing else to feed on!

Shrimps. In addition to cleaning up your tank, they can also serve as food for the fishes in your aquarium.

Most fish keepers forget to feed the bottom feeders thinking they are sustained by the left-over feed and debris, this is not ideal. At least once in a week, try to also feed the bottom feeders

In addition to having a cleaning crew, it is also recommended that you change about 25-50% of the water in your tank every week to keep your tank clean. You also have to be careful when doing this because changing the water in the tank too often can result in a chemical imbalance.

Other compatible fishes

This list would help you know the kind of fishes that can peacefully cohabit with your tetra:

Calm fishes-Tetra fishes are known to be calm and peaceful, so they thrive well with other calm and peaceful fishes such as guppies, corydoras catfish, harlequin rasbora and the halfbeak.

Minimum midline swimmers- Another thing to keep in mind is that tetra fishes are midline swimmers, so most of the time, they are found swimming at the middle of your tank, avoid keeping them together with too many midline swimmers as this could result in overcrowding. The guppy is an example of a top swimmer

No fin nippers- like tiger barbs.

Other small fishes- like guppies, platys, mollys. Avoid other large fishes like Oscars and gouramis as they would only feed on them

Bottom feeders- Fishes in the cleaning crew (including the shrimp and crayfish) can successfully cohabit with your tetra.

The best thing to do is to avoid placing the tetra fish together with another fish that is big enough to feed on the tetra fish.

The Tetras are an exceptional species of fishes and their docile temperament makes them an excellent choice to include in your community tank.

Although their lifespan in the tropics which is their natural habitat is about 8 to 10 years, if they are properly cared for, they can survive for as long as 5 to 8 years in your community tank.

The small size of the tetra fish is compensated for by its great beauty and functionality, it would be very beneficial to your fish tank community if you include a school or two of them in your fish tank!