How many fish in an aquarium?

Do you have an aquarium and are you wondering how many fish can you fit in? So, this guide is here to help you determine the ideal number of fish for your aquarium and not overcrowd your fish's living space. The fish that will serve as examples in this article are obviously not exhaustive.

You should know that an aquarium that is too small or overcrowded greatly increases the risk of problems in it: Well-being and potential lifespan of fish greatly reduced, fouling of the basin faster, various insufficient resources, etc.
The quantity and therefore potentially the number of species that you can put there will vary, depending on the volume of the aquarium . Indeed the larger the aquarium, the higher the possible quantity will be.

The "small aquariums":

If you have an aquarium between 10 and 50 Liters , the maximum number of fish will obviously be quite limited. But it is still possible to place some fish there. For example, if you want to dedicate your aquarium to a Fighter, for example , there will be no space concerns as long as he remains alone in it.
Some couple fish can also live together in volumes of 10 to 50 liters. Some species of Killies such as Cape Lopez Killies for example can be satisfied with a minimum of 20 liters for two individuals , although it is obviously advisable to provide them with more space for their well-being. Small shrimps such as members of the Neocaridina family can also be integrated into aquariums of this volume, the ideal being five individuals for about twenty liters. There are also many other species that can live in small volumes.

"Medium" sized aquariums:

Then come the aquariums located between 50 and 100 Liters . These volumes already make it possible to increase quite significantly the number of fish that you can place in it, including certain fish that live in schools.

The previously mentioned Fighter can now live with one or more females (especially no other male!) and it is also possible to make it cohabit with certain species in a 100 Liter aquarium, be careful however not to mix it with other other fish without having inquired about the species tolerated by it. If you have any doubts, do not hesitate to ask a specialist.
Fish that live in small groups such as Guppy are now entering this volume range, you could indeed fit 5-6 in your aquarium.
Shoal fish such as Neon can also be integrated into an aquarium of about 100L with a group of about fifteen individuals, school fish generally require a minimum of ten individuals to be able to live in good conditions.

"Large" size aquariums:

Then, for aquariums with a volume above 100 Liters, the possibilities become really interesting if you want to have an aquarium containing multiple different species present in a certain number.

Obviously between an aquarium of 100 Liters or 400 Liters the quantities of possible fish will be very different.
As for shoal fish such as neons, their quantity can be increased proportionally, however, be careful with species that reproduce quite easily, you could end up with an overpopulation quite quickly. It is also possible to mix 7-8 Guppies with around twenty Neon Tetra for example.
Why not mix several species with Corydoras for example? The different species of this family feed on the waste found in the aquarium, which will allow you to bring life to the bottom of it while preventing the arrival of a deposit. The Bronze Corydoras , for example, live in groups of more or less eight individuals and can mix with other species peacefully.

Some fish also need a lot of space, but for only one individual. For example, some species of Pleco need a hundred liters for a single individual , which makes them fish that cannot be found in any aquarium.
It should also be taken into account that semi-territorial fish, which can therefore tolerate certain other species, risk being more aggressive if their living space is not adapted to their size needs.

The Nigro , for example, are fish that like to live in pairs in a minimum of 150 liters, but since they are fish that can be quite territorial, it is not recommended to mix them with other territorial species. They are also known to dig in sand, so choose an aquarium and neighbors that suit the behavior of these fish.

In the end, the most important points to take into account concerning the quantity of fish that you can place in your aquarium are:

• The liter of the aquarium, the larger the aquarium, the more species and the number of individuals possible to integrate into it will be important. It will also increase the possibilities of inter-species cohabitation within your aquarium.
  
  
• The kind of fish you want to get, whether it is solitary fish or gregarious fish (which need food in groups), especially shoal fish, their living space needs will be totally different, the schooling fish generally requiring more space and sometimes some fish like Plecos (discussed above) require a lot of space for a single individual. If they are territorial fish, it is also necessary to be sure to find out about the species they can mix with and adapt the population accordingly.
  
  
• The number of different species you want to have in a single aquarium. Indeed if you want for example to have 4 different species in a 200L aquarium, you may have to choose species that do not need to be present in very large groups. Or non-territorial solitary fish with shoal fish.
  
  

For all that concerns the possible cohabitations between the species, we advise you to ask your retailer or a specialist according to the fish which interest you, in the same way for the litration necessary for their well-being.
We hope this guide has helped you find the amount of fish you are heading towards.