Can a Fish Swim in Milk? [What No One Is Talking About]

Can a Fish Swim in Milk?

Sure, a fish can swim in milk. Milk is a liquid having the same viscosity as water. Actually, like humans, milk contains mostly water.

The fish can be swimming in milk, but the fish won’t survive for an extended period. Milk also contains other ions with much higher levels than water.

The solution’s tonicity will not be beneficial to the life of fish. Although the milk is mostly water, it’s not a problem because it’s an extremely delicate balance.

For humans, breathing mostly oxygen and a bit of carbon monoxide might seem okay because it’s mostly oxygen however, carbon monoxide binds to hemoglobin, with around 250x the affinity that oxygen has.

Thus, fish die from the lack of oxygen. This isn’t the best metaphor, but I hope it does get an idea across.

The most significant issue for fish in milk is that they will not be in a position to perceive. This shouldn’t be an issue in the fight against predators, since, in large part, they depend on their lateral line to identify enemies, which they aren’t likely to see in milk. However, they won’t be able to hunt for food until it moved.

Another issue is that fish haven’t evolved to live in milk, so they’d soon get bacteria that would be unprotected.

A quick splash of a few seconds or perhaps minutes in milk, and then back into the tank water (like maybe drinking milk in water) is probably not a bad idea however, any prolonged time in milk is likely to not be a good idea for them.

Can a Fish Survive in Milk?

Fish cannot live in milk. Fish are unable to breathe well in milk because of the low oxygen levels in the milk and also the high level of impurities in milk. Thus, fish can get buried in milk within only a couple of minutes.

Fish cannot live when they are exposed to different environments like vodka, milk, vodka, or other liquids due to the fact that their bodies are not designed to withstand environments other than water. Freshwater fish are not able to endure in saltwater and the reverse is true.

Have you ever wondered could fish be able to swim and live in coke, milk beer, coke, or other liquids other than water?

Before we go for milk, we should first learn how fish breathe and live within the waters.

Can a fish swim in milk? Yes, it is possible for fish to swim within milk however they’ll die pretty fast since milk doesn’t contain oxygen, nor any amount of hydrogen or survival necessity to live. They’ll panic and eventually end up dying. They need water, not tea, milk soda, coffee, or soup. Don’t place live fish in milk!

Fish do not have lungs as humans due to the fact that human lungs require to be dry in order for them to function. If fish have respiratory systems like humans, then water in their lungs will be filled because they breathe underwater and must draw oxygen from the water, unlike humans, they extract oxygen out of the air.

Thus, the lungs will not perform as well for fish that swim underwater. Fish have gills that allow them to breathe underwater. The gills of fish help draw oxygen from the water. In the process of breathing for fish, the water initially enters through the mouth before it goes through the feathery filaments of the gills.

Gill filaments are thin threads similar to protein structures. They also have a capillary system that offers large surfaces to exchange carbon dioxide and oxygen.

The oxygen absorbed by the filaments of the gills circulates throughout the body through the assistance of the heart pump in a fish.

Once the conversion of carbon dioxide is completed, carbon dioxide-rich water is released from the body via the gill flaps.

This way, fish absorb oxygen and removes carbon dioxide so that they can live in the water.

Milk is made up of nearly 87% water however it isn’t the ideal habitat for fish to live in. Fish can swim freely in milk as it has a density 1.2 times greater than that of water and also it has the same viscosity as water.

Let’s take a look at conditions that create the most uninviting environment for fish.

The presence of fats, lactose, and protein molecules in milk can reduce the amount of oxygen dissolved.

A large number of fats, minerals proteins, minerals, and other substances could clog fish’s gills, causing air suffocation that fish breathe.

Another challenge for fish is the visibility of the milk. This will make it impossible for the fish to locate food within the milk in the event that it does not move. Also, it is possible the fish may contract a disease because they’re not developed to live in milk.

Milk can be considered an environmental pollutant that is as well as pollutants within the atmosphere. We have learned that the existence of contaminants in the air can cause breathing problems and could trigger various respiratory infections in people.

Similar to fish, milk can be a source of pollution water, making it hard for fish to breathe and live.

Like milk, other liquids like beer and coke will be hard for fish to survive because they have more sugars, minerals, fats, carbohydrates, and other substances when compared to water.

Most animals have developed and survived in accordance with their environment, so should any animal be exposed to any environment that is not its own it’s very likely that it will not survive.

Let’s think about if humans were transferred to Mars, with different conditions for the atmosphere. Are you sure that humans will endure? Yes, it’s tough for us to survive and it may take our time to adjust to the mars conditions. Similar to this fish could drown in other liquids from outside that fish aren’t well-prepared.

Can a Fish Survive in Milk?

Interesting Facts:

Freshwater Fish Cannot Survive in Saltwater and Vice Versa

This is due to its tonicity. The saltwater solution is known as a hypertonic fluid where the concentration of salt is higher in oceans when compared to the level of salt found in the fish’s body.

Because of this, fish are able to lose water to the environment through the process of osmosis. To stay alive in saltwater, fish need to increase the amount of drinking water they consume.

Freshwater is a hypotonic solution, in which the salt concentration in the body of the fish is greater than that of the reservoir for freshwater. Because of this, water constantly enters the body of the fish through the process of osmosis.

In this instance, the fish must often urinate. Freshwater and saltwater fish have developed their bodies to adapt to the environment in which they live.

If we place freshwater fish in saltwater, they will suffer from dehydration as their bodies aren’t designed to consume more water.

The same saltwater fish can be killed in freshwater as their bodies will become filled with water because their body isn’t in the habit of frequent urination.

We know that all animals, including fish, have evolved according to their environment and it is difficult for them to live when there are any changes in their surroundings or if they are exposed to any new environment.


Do Fish Drink Milk From Their Mother?

Can we feed fish with milk? It’s not possible. Fish don’t have mammary glands and therefore are unable to lactate.

Which fish gives milk to His baby?

The vivid Amazonian discus fish create milk-like mucus that they feed their children (fry). Both parents make the slime by removing their skins, which is not just nutritious but also has beneficial bacteria that help to create the microbiome of the fry’s gut.

Does Milk Hurt Fish?

Since milk contains a significant organic matter content, it could cause fish deaths in the streams. The oxygen levels in the stream decrease as the bacteria break down the milk. If milk concentrations are very high, the oxygen sag may kill fish as well as other aquatic creatures such as crawdads and insect larvae according to Iowa DNR.

Can a Fish Swim in Milk? (Summary)

Fish live in water and skim milk has 90.4 percent water, meaning that could fish exist or even breathe in milk? …? The variations in acidity and the dissolved oxygen level, not to mention the proteins, fats carbohydrates, as well as other minerals present in milk that could block the gills of the fish, could quickly cause problems.

It is possible for fish to swim within the milk. It’s a liquid that has the same viscosity as water. A quick splash of a couple of seconds or even minutes in milk before going back to water (like maybe drinking milk in water) likely wouldn’t harm however, any prolonged time in milk is unlikely to be beneficial for them.


Dibyajyoti Bordoloi is the creator and author of, a third-generation experienced fish keeper and owner of a successful pet breeding farm. He is also a member of the Center for Wildlife Rehabilitation And Conservation (Assam), the Marine Aquarium Societies of North East India, and the Kaziranga Nature Conservancy of Assam.