Do Fish Pee? The Ultimate Guide To Excretion In Fish | Kidadl

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Do Fish Pee? The Ultimate Guide To Excretion In Fish

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Several people who are new to keeping fish as pets, or visiting an aquarium for the first time wonder if fish urinate in the water.

Fish poop and pee in an aquarium is a natural process of excretion of waste. Fishes cannot escape the surface of the water to excrete their waste and keep the water clean.

It is a well-known fact that most fish cannot survive outside of water. These animals live and die and complete the entire cycle of their life while staying underwater. Likewise, even the primary processes like eating and excretion take place under the water. This article will explore how the fish who live under the water gets rid of their organic and biological waste, why it does not pollute the water of the ocean, and whether the waste is harmful or useful for surrounding marine life. After reading this article written to help you understand about feeding, peeing, and pooping is done by fishes in the aquarium, also check do fish have eyelids and do fish have livers?

Do fish pee in the water?

The very simple answer to this question is yes, all fishes pee and poop in the water, in the sea, ocean, river, tank, aquarium, or wherever these animals reside. Peeing and pooping is a natural process of excretion of waste that all living beings have to go through.

There are several types of processes for excreting waste, which vary from single-celled organisms to multicellular organisms like birds, fish, and humans.

One would naturally wonder further whether this waste produced by fish is harmful to marine life or not. The answer is no, it is not harmful. Rather, fish urine and fish poop serve as a rich source of ammonia, nitrogen, and phosphorus for the coral reefs. Coral reefs are a collection of various aquatic plants growing together. The coral reef is mainly dependent on the fish which reside within their colonies, for their maintenance and as well as nutrition. The coral reef extracts the nutrients like ammonia, phosphorus, and nitrogen from the fish pee in the ocean as a source of food.

Several fish excrete waste in different manners. Some fish urinate through their gills, while other fish have small openings for excreting called a urinary pore. Further, saltwater fish and freshwater fish have different mechanisms for excretion due to their various nutritional needs and the environment in which these animals live. For example, freshwater fish need a lot more salt in their system compared to saltwater fish. Hence, the bodies of freshwater fish absorb as much water as is necessary for them to keep functioning.

Compared to freshwater fish, the bodies of saltwater fish are adapted to excreting the excess salt content which is taken from the saltwater which it is surrounded by. Hence, it is observed that the pee or fish urine of freshwater fish is a lot more watery compared to saltwater fish, which have concentrated urine that contains mostly salt and ammonia particles rather than water. Likewise, due to their different bodily mechanisms, it is observed that most saltwater fish tend to excrete through their gills, while the freshwater fish urinate through the urinary pore.

While any conclusive evidence regarding us drinking fish pee inadvertently is still not available, it is advisable to avoid intake of water when you are out and about water bodies with fishes in them. You must treat such water before ingesting it if you wish to avoid drinking fish pee.

What does fish pee look like?

Typically, fish pee does not look anything different from a normal liquid. Fish tend to pee once or twice a day, and the type of pee usually depends on the fish. Saltwater fish urine is a little more concentrated and thick compared to the urine of freshwater fish. Fish may pass urine through their gills or urinary pores.

On the other hand, fish poop is a lot more visible than fish pee. The excretion of fish generally includes undigested food waste, bacteria, and salt extracts. The color of it is said to vary according to the type of food which the fish consumes. If your fish eats a pea-based feeding diet every day, the poop may appear a dark shade of green like peas. Peas are also said to help in the cases where your fish is suffering from constipation. If your fish eats fish feed every day, the waste products may appear red due to the abundance of bloodworms in the fish feed.

Either way, if you notice any sudden change in color in the poop of your fish without any changes in their diet, it could indicate health problems or a lack of nutrients in your fish’s body. Waste products of fish who are ill may appear gray or white in color. Further, fish poop also varies in texture, volume, and odor. Hence, it is necessary to keep a watch on the amount and frequency of your fish’s poop and excretions as it can be an indicator of the health of your fish.

It is important to replace and clean water in a tank that contains excess ammonia.

How often do fish pee?

The digestive system of most marine creatures, including fish, both saltwater and freshwater has evolved in a manner where a simple digestive process takes a lot of time and energy of the animals.

Likewise, in the case of fish, the food can remain in the digestive tract of its body for a whole day before it can excrete it. Normally, fish tend to pee once or twice a day, as the fish species do not need a lot of water to survive.

Hence why there could be a delay between the intake and excretion of the food which the fish eat. Freshwater fish tend to absorb the nutrients of salt for the maintenance of health. The pee of fish can fertilize several species of algae and coral reefs with nutrients like ammonia, nitrogen, and phosphorus. Fish urine does not contain a lot of urea, rather it is abundant with nitrous oxide, which helps aquatic and marine life thrive from its nutritional source. The skin and scales of the fish are evolved to give them the ability to release their liquids through the gills, and their permeable skin makes them able to pass the waste through their gills.

Hence, fish do not pee often, only once or twice a day. On the other hand, fish do not poop a lot as well. A fish that is fed regularly every day, may poop once every two days. A fish that is fed a little irregularly may take more than two days to excrete regularly. Further, there is a danger of this food getting stuck in the intestine of fish, which is very often found in fish who are overfed. Hence, it is recommended that fish who are fed frequently should be given a break every 8-10 days to catch up with their metabolism. This also helps in cases where the fish is suffering from constipation and helps them poop.

As a responsible owner, you must clean the surface of the aquarium from the outside or inside. For example, in order to maintain the hygiene inside the tank, you must replace water regularly.

Fish Excretion Process

Just like humans, fish have a set of two kidneys as well. Depending on the types of fish, the kidneys can vary in size, shape, and position. Fish like eels have an elongated set of kidneys, while others have more compact ones.

The head kidney is responsible for filtering the waste which passes through the gills and the kidney located at the posterior filters the waste which is to be passed from the urinary pore found in many fishes.

As explained in the previous answer, the digestion process of fish is pretty slow compared to other animals. The intestinal tract of fish can take several days for the food to digest. Simple, breakable molecule foods can be digested by fish in a day or two but more complex foods take a longer time to digest. Hence, it is necessary that a lot of fibers are included in your fish’s diet.

Naturally, fish that live in the ocean, lakes, or seas find all the nutrients which are essential for their growth, but fish that live in a tank or aquarium may not come across these nutrients easily. Hence, it is necessary to feed your fish with health supplements and a natural diet that can ensure the intake of necessary fibers in your fish’s body.

As fishes are always surrounded by water, their body is adapted in a way where their excretory system does not allow the necessary water content to be absorbed out of their body by osmosis. For this, the fish’s skin is impermeable to saltwater which allows them to excrete certain wastes and salt through the gills. Freshwater fish have an even lesser chance of coming across salt which is an essential nutrient for their growth. Hence, these fish excrete waste in the form of nitrogenous substances of ammonia and urea which serve the function of saving the water inside their bodies.

Thirst is generally explained as the need to drink or intake water because the body feels dehydrated. Water serves the purpose of providing hydration to the cells in our body which carry out the functions like circulating blood, filtering blood and digesting food, etc.

The body mechanism of fish is built in such a manner that these functions are fulfilled not by carrying out the act of gulping or drinking water, rather, these animals have gills to intake the necessary amounts of water for extracting the elements for breathing and passing out the waste through the gills as well. Fish have different body processes for diluting their blood or keeping it in the balance of salt quantities, in the case of saltwater fish. Hence, unlike humans, fish do not feel the need to drink water and hydrate themselves. Rather, if the fish species do drink the water, it might cause some bodily imbalances or problems.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked our suggestions for do fish pee then why not take a look at do fish have tongues, or do fish need oxygen.

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Kidadl Team

The Kidadl Team is made up of people from different walks of life, from different families and backgrounds, each with unique experiences and nuggets of wisdom to share with you. From lino cutting to surfing to children’s mental health, their hobbies and interests range far and wide. They are passionate about turning your everyday moments into memories and bringing you inspiring ideas to have fun with your family.

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