How Many Fish Can You Keep In An Aquarium Fish Tank?

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How-many-fish-can-you-keep-in-an-aquarium-fish-tank

How many fish will go in my aquarium? As many as will fit in, only they won’t survive!

There is no rule of thumb or standard formula for calculating how many fish to put in an aquarium. The amount of fish is different for every aquarium. The maximum number of fish in an aquarium depends on so many factors that a standard rule of thumb can only be used as a guideline.

 

Tank Size

It is better to determine for yourself how many fish can be in your aquarium than to cling to a rule of thumb or formula. The maximum number should be tailored to the swimming space in the aquarium and the behavior of the fish and the size of the aquarium. Some fish species need even more water than others. Therefore, a rule of thumb to calculate the number of fish is not the right method to use.

Obviously, the size of the tank is important. The larger the tank the more tropical fish you can keep in it. A freshwater aquarium with many plants and a high flow rate can hold more fish. The fish species and behavior also determines how many aquarium fish will go in it. A fish is often bought small in an aquarium store. The young fish will become an adult. You should therefore take into account the length of an adult fish.

 

Filter system

With a properly functioning filter system, more fish can live in an aquarium. As long as there is sufficient water flow. Sufficient water movement at the water surface is important. This allows the water to absorb oxygen from the air.

The more fish you have, the more oxygen is consumed. An oxygen stone often does not work as well, because it breaks open the water surface and thus the oxygen can escape again.

 

Different fish species

There are many aquarium fish that cannot be kept solitary. You need to find out what kind of aquarium fish it is that you would like to have. Most fish live in groups or must be kept as pairs. These are many more than you might initially think. The question of how many fish can be kept in aquariums must of course take this into account.

 

School fish

With a school fish, you have to take multiple specimens because this fish lives in groups. If you place a single specimen of a shoal fish in your aquarium, the shoal fish will not feel comfortable. He will not exhibit natural behavior. The fish will become stressed and eventually die. School fish should be kept in groups of at least 5 specimens, but preferably more.

The larger the group, the more at ease the fish feels and the more natural behavior it exhibits. A fast-swimming schooling fish should never be placed in a tank that is too small. Aquarium fish can die if they have too little swimming space, while overcrowding is often thought to be due to wrong water conditions.

 

Pair fish

There are also fish species that should be kept in pairs. These fish need to live together as a pair. Like schooling fish, pair fish will get lonely and disappear if placed alone in the aquarium.

 

Many fish should be kept in a group or as a pair. In some aquarium stores, schooling or pair fish are easily sold as singles, without asking if you already have more such fish at home. So check carefully for yourself what kind of fish it is and buy multiple specimens of the fish species if necessary.

 

Reproduction

There are fish that can reproduce quite quickly, think of guppies for example. It is best to take this into account. For example, you can add larger fish to keep the population in check, or you can only take them of the same sex so they cannot reproduce.

Should you only want guppy females, keep in mind that they can already be pregnant. Avoid this, otherwise you might still have males among them and the population in your tank will only increase.

 

Different water layers

Fish live in different water layers. An aquarium can be divided into three different water layers. The middle zone, if the aquarium is quite high, can again be divided into separate water zones. The aquarium water zones are:

 

  • The upper part
  • The middle section
  • The lower part

To ensure that a particular aquatic layer does not become overcrowded, you need to figure out in which aquarium fish will move. There are surface fish that are mainly in the upper water layer and very occasionally in the middle section. There are bottom-dwelling fish that use only the lower water layer. Catfish are bottom dwellers but there are also snakes, the mudskippers that live mainly on the bottom.

Thus, you can choose the right aquarium fish for each water layer. At night, fish can change water zones. Some fish are in different zones at night. A zone can then become overcrowded at night and cause problems.

There can also be a problem if a fish likes to spend the night on the bottom and a lobster lives there, for example. If the fish then gets too close to the lobster with sharp claws then it can become the prey. Keeping the fish in the right water zone is important both during the day and at night.

 

The behavior

Now that we know all this, we need to look at the behavior of aquarium fish individually. There are aquarium fish that do not like to swim near other species. Some aquarium fish are quite aggressive toward each other or other fish species. In addition, you have fin biters to consider.

 

Day and night

When the lights in the aquarium go out, the fish will go into a hibernation mode. The fish are resting to build up energy for the other day. With overcrowding, not only do they get little rest during the day, but also at night. This can cause stress, disease and even death.

Overpopulated aquarium

Overcrowding should be ruled out. You quickly tend to put in more fish than are actually healthy. Never take all aquarium fish at once. First study carefully how the new aquarium fish behave. If there is enough space left, you can add new aquarium fish. Make sure the aquarium does not get too full, an overcrowded tank is not pretty and can cause you a lot of problems.

Too many fish causes stress, too much stress can cause a fish to get sick and die. Ichthyophthirius Multiliis or white spot disease is the most common fish disease. White spot gets a chance especially with reduced resistance of the fish. Reduced resistance is often caused by stress.

 

Quantity rule of thumb

How many fish fit in aquarium.

So how many fish fit in aquarium cannot be calculated with a simple rule of thumb. Rather sit on the low side than the high side. It is much nicer to see a fish swimming around in its element than to watch a fish under stress, eating little and eventually dying from it.

 

Ben
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