Do Fish Get Thirsty? Amazing Facts!

Do fish get thirsty? It’s a question that’s been asked by thousands, and the answer is not exactly a yes/no one.

The question of whether fish feel thirst is an interesting one, considering that humans experience it a lot. Fish live in water. So, do fish experience thirst? Do they experience some kind of fluid loss and dehydration? Do they need water at all?

Fish are among the most interesting creatures in the animal kingdom. Naturally curiosity about fish always prevails.

Many people have several questions crossing their mind after watching a fish in water. So, let’s look at the answer to the question and incidental aspects too.

Do Fish Need Water Internally?

Fish do need water to live because they need essential minerals and salts that they can only gotten from being in contact with water.

They also need to maintain a balance of electrolytes and other chemicals in their bodies, which can’t happen without the right amount of water intake. So, irrespective of whether it is a saltwater or a freshwater fish, they do need water for purposes other than oxygen. The manner in which it is absorbed may differ, the body mechanism may vary, but they do need water.

What Is Thirst?

What is thirst?

Thirst is the need to drink water and quench a parched mouth. A feeling of a dry sensation in the mouth which can be eased by drinking water.

When do we feel thirsty?

A person may feel thirsty when they have not had enough to drink for some time, or when their body needs fluids because they are dehydrated, or for other reasons such as exertion or exercise.

Thirst is a physiological feeling that occurs when the amount of water in our bodies becomes too low. It’s not just about drinking water—it’s about attaining relief by consuming liquids.

Thirst is a signal by the body that it needs water.

So, do fish go through all of this? Let us find the answer to it? gif maker 2022 10 08T210653.244

What Is Homeostatic?

Homeostasis is the maintenance of a constant internal environment within the body. It’s the ability of living organisms to regulate their internal conditions and make sure they stay within normal ranges, even when external conditions change.

Fish have homeostatic mechanisms that help them maintain salt levels in their bodies.

Having understood these concepts, let us move on to understand fish and thirst in fish.

Freshwater Fish Absorb Water

Freshwater fish absorb water through their skin and gills, through which they get essential minerals and salts.

Freshwater fish need water in order to stay hydrated and alive. The amount of time that it takes for a fish to absorb water will depend on its size and species.

The gills are used to absorb oxygen from the water, which they then use to breathe. Essential minerals and salts are also absorbed at the same time.

In addition to providing them with essential minerals and salts, this process also allows freshwater fish to use the water as a natural filter for removing waste products from their bodies.

They do not need 100% of the water that they absorb; instead, they only need enough to maintain homeostats.

Do Fish Get Thirsty?

Saltwater Fish Drink Water

Yes, saltwater fish drink water. Unlike freshwater fish who only absorb water, saltwater fish actually drink the water. The reason they need water is the same. They need water to get essential minerals and salts.

Saltwater fish are animals that live in oceans, seas, and other large bodies of water with high salinity.

Seawater is saltier than the blood of most saltwater fish, so it’s necessary for marine life to drink water. In fact, they can’t survive without it.

They excrete excess salts through their kidneys or gills. gif maker 2022 10 08T210653.244


Osmoregulation is the process of regulating the electrolytic balance of a cell, tissue, or organism. It occurs in all cells and is essential for life.

Osmoregulation in fish involves the movement of water from one side of a membrane to another. It is achieved by controlling the amounts of salts retained and excreted by the fish.

In other words, it involves the absorption of water and the excretion of excess salts.

Osmoregulation is also the process by which fish maintain the concentration of ions in their internal fluids. It’s a way for animals to keep their internal fluids from getting too diluted or concentrated, and it’s critical for their survival and maintenance of Homeostats.

Difference Between Osmoconformers & Osmoregulators

Osmoregulators and osmoconformers are two types of fish that differ in how they maintain body fluids.

Osmoconformers match the body to external environment, while osmoregulators maintain stable body levels unconnected to external environment.

Osmoregulators are fish that can survive in a wide range of environmental conditions.

Osmoconformers are animals that respond to changes in external environment by altering their internal conditions.Osmoconformers are only marine, while freshwater fish can be osmoregelators or Osmoconformers.

Osmoregulators constantly regulate their body in order to maintain a constant internal environment.

Osmoconformers on the other hand have the advantage of being able to survive in a wide range of environments.

Some fish like Salmon move from saltwater to freshwater and back. These fish are able to adapt to both ways depending on where they are. gif maker 2022 10 08T210653.244

Excretory System In Fish

The kidney is a very important organ in fish. The kidneys process the water, minerals and salts that are absorbed by the fish.

It also regulates the amount of salt that goes into the bloodstream. Fish have two kidneys, one on each side of their body.

The entire osmoregulation is dependent on the kidneys whether freshwater or saltwater.

Fish have two types of kidneys, the head kidney and the posterior kidney. The head kidney is responsible for filtering wastes from water that passes through gills. The posterior kidney filters waste through urine and passes them out of the body.

Can Fish Get Dehydrated?

Fish can get dehydrated, just like we can.

Loss of electrolytes can occur in fish too. This can cause dehydration even though they live in water. It can even happen due to kidney failure.

If you keep your fish in an aquarium, then you will need to change the water regularly so that it does not become polluted with waste produced from the fish themselves (which would make them sick).

Fish are commonly thought to be the only living creatures that live in water and don’t get dehydrated. But while they do have access to water, fish can also lose electrolytes through their gills and skin. This loss can lead to dehydration, even though fish live in water.

And just like humans, fish can become dehydrated if too much water leaves their bodies or if not enough water enters their bodies. gif maker 2022 10 08T210653.244

Fish Do Not Get Thirsty

Do fish get thirsty?

The short answer is: not in the way humans do.

Fish need water and they take in water. Either through their skin, gills or through drinking. Osmoregulation and osmo-conformation ensure that fish do not get dehydrated or thirsty. So no, fish do not actually feel thirst.

Fish need water and they take in water, either through their skin, gills or through drinking (in saltwater fish). This ensures that fish do not get dehydrated or thirsty. So, no, fish do not actually feel thirst.

This means that while they may need to drink more water than us, they don’t actually feel thirst like humans do. gif maker 2023 04 22T201514.431

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A lot of people think fish get thirsty, but in fact they don’t. This is because they have a very efficient system that allows them to regulate the amount of water in their bodies at all times. The most important factor here is osmoregulation which allows fish to live in both salt and freshwater environments without any problems whatsoever!

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