jacilluch, CC BY-SA 2.0, via Wikimedia Commons

The Glass Catfish, which is scientifically known as the Kryptopterus vitreolus is one of the most common aquarium fish species, known for its beauty and peaceful social nature. It has multiple trade names including the Ghost Catfish and Phantom Catfish. It is known as the Glass Catfish because its body is transparent. This makes them look even more beautiful. It is a freshwater species, native to East Asian countries. Glass catfish are found in many small rivers across Thailand, and Malaysia in the Isthmus of the Kra peninsula.

It likes to live near the banks of rivers, ponds, and lakes in the area. Their transparent bodies sometimes reflect light in a rainbow pattern. Unlike other catfish that spend most of their time sucked onto rocks, this fish species likes to swim. Apart from that, it is also not a big species like most of the other Catfish are, and it is peaceful as compared to most other fish from this family.  It is known for being shy. It avoids fights and runs into places where it can hide. This fish is a slow swimmer and it swims with other members of its species.

Basic Facts Table

Lifespan7 to 8 years
Size5 Inches
ColorsTransparent, silver, black.
Freshwater or SaltwaterFreshwater
Care LevelModerate
CompatibilityPeaceful Community Tanks.

Tank Companions

As you know the Glass Catfish is a peaceful species that likes to avoid fights and does not attack other members of the tank, it should be paired with the other fish species of the same nature. There are a lot of peaceful fish species that you can put in the same tank as the Glass Catfish. But you will have to make sure that the fish that you are adding inside the tank is not too small that it can get eaten by the Glass Catfish.

This fish does not like being alone inside the tank. Meaning that you will have to put other members of its species inside your tank. Keeping a single Glass Catfish can cause health problems for your fish. It has been reported that this fish develops anxiety and depression if it is kept alone. But if it is kept with the members of its species, it develops a schooling behavior which is a treat to watch. That is why it is recommended that you keep them with the other members of their species. If you are building a community tank for the Glass Catfish, make sure that all the fish that you are adding to that tank are peaceful and have a similar size.

Also, do not add any aggressive fish in aggressive fish species or large sizes in their tank. This is because the aggressive fish species might attack them for dominance inside the tank. These are slow swimmers and some fish species like to nibble the fins of slow swimming fish. So, make sure that you are not putting any fish species that would like to eat their fins. It would not hurt the fish that much but it can cause infections and diseases and that is why you should keep them in a peaceful tank.

Here is a list of the peaceful fish species that you can add to the tank of Glass Catfish.

  • Kuhli Loach
  • Cory catfish
  • Peaceful Gouramis.
  • Peaceful Guppies.
  • Most Mollies
  • Swordtails
  • Celestial Pearl Danios

You need to look for three things when deciding a tank companion for the Glass Catfish tank. First, make sure it is a peaceful fish species and is completely non-aggressive. Second, make sure that the fish you have selected has a similar size. You cannot put a large fish with them as they might be bullied and you cannot put very small fish with them as they might try to eat them.

Third, you need to make sure that the fish you are selecting likes to live in similar conditions as the Glass Catfish. Because if that fish likes a different type of environment, you will not be able to pair it with the Glass Catfish. Most cichlids, sharks, barbs, and Oscars do not make a good companion for the Glass Catfish because all of these are aggressive.


Grouping Asian Glass Catfish

The Glass Catfish is transparent, but some parts such as eyes, and head give a blackish tint. Also, the parts where the internal organs of the fish lie give a bluish appearance as well. They reflect light from their bodies and that can sometimes create a rainbow pattern on their bodies. It has two long barbels that they use for sensing the environment. The average size of these fish is about 8 cm or 3 inches but they exceed it more often and can reach up to 5 inches in length and two inches in width.

You can see the bones and internal organs of the fish from outside. It appears to have the main bone that goes from the head towards the tail fin. This main bone has multiple branches that go up and down in the fish’s body. It creates a beautiful line appearance. The head part as mentioned above is partially covered in black. It has two bulging eyes on the sides of its head that cover a larger portion of their heads. Apart from the head, they also have a long and pointy mouth that they use for feeding and sucking on stones.

It is transparent because it lacks color pigmentation and scales on the body. Organs of this fish are located near the head which is why the head part of the fish is very thick and blackish. Meanwhile, the rest of their bodies are very thin and they appear like elongated arrows. If your fish falls ill, it would be easy for you to detect, because their bodies turn white during the illness. It is known as some of the only small fish species with completely transparent bodies that are seen inside the aquariums. Other fish with a similar appearance or either too big or too small.

Origin and Natural Habitat

This species is native to East Asia and is known for living in the shallow waters, and near the bank areas of the rivers in Thailand, and Malaysia. Apart from these areas, it is also seen in the areas of the Cardamom Mountains where rivers flow from the mountain heights towards the Gulf of Thailand. It is a freshwater species, meaning that it stays in the river areas but does not enter the saltwater region of the Gulf of Thailand.

In its natural habitat, this fish species likes warm temperatures, neutral water, and less hardness inside the water. The chemical composition of water in this area is slightly different from the rest of the world, and it favors their growth. Apart from swimming near the sides of the river, it can also swim inside the main flow of the river. But that behavior is only seen in adults of four to five inches size. Small fish like to stay in places where the flow of water is moderate.

Also, the sides of these river basins where Glass Catfish lives are covered with a lot of plantations. This plantation acts as a food source for the Glass Catfish and shelters them from predators. Their transparent bodies help them hide from the eyes of predators that can detect different colors inside the partially dark waters. In its natural habitat, it likes to form groups and swims in those groups. If you are planning on buying the Glass Catfish, then you will need to make sure that you provide them the right conditions to live, otherwise, they would not be able to reach their expected lifespan.

Glass Catfish Lifespan

The Glass Catfish can live up to 8 years in captivity if the conditions are perfect. But if the conditions are not right, they would die within a few years. This is because it is one of the sensitive fish species that does not like any type of changes in its environment. So, if you are planning on buying and keeping the Glass Catfish in your aquarium and you want them to live long and stay healthy, you will have to make sure that you provide them with the right type of conditions.

Habitat and Tank Conditions

As mentioned in the paragraph above, if you want your fish to live long and stay healthy, you will need to provide them with the right conditions. The right conditions are similar to their natural habitat and that is what helps them live long inside an aquarium. So, when you start building a habitat for them, you will have to start with the tank. There are a lot of types, sizes, and shapes of the tanks. You should select the tank with a square shape and with more height. This is because they like to live in the middle layer of the tank and hence need more water in the middle layer. The size of the tank for your aquarium is very important. You need to pick a tank that is large enough to provide the required space for every member of your tank. There are a few things that you need to keep in mind while determining the size of the tank.

You need to know the number of fish that you would put inside that tank. For example, if you are making a tank of the Glass Catfish only and want to put 6 individuals in the tank, you can use the 20-gallon tank. But if you want to put more fish inside your tank, you will need to make sure that you get an even bigger tank. A 30-gallon tank is known as good for a healthy population of Glass Catfish. Also, if you are building a community aquarium where you want to put more fish, you will need an even larger tank based on the number of fish of different species that you would put in that tank. You also need to know the fish/gallons ratio of the fish species to determine the right size of tank for your fish. Once you have selected a tank it is time for you to start creating the right type of environment or habitat inside that tank.

You should start from the bottom layer. Use soft and treated sand for the bottom layer. You can put some rounded stones as well, but make sure that everything you are putting inside the water is cleaned and has been washed and disinfected. You will need some plants because the aquatic habitat of this species is covered with a lot of plants. You should put the hornwort or java moss inside the tank. They grow upwards, meaning that they will provide cover even in the middle and top layers of the tank. You can put some driftwood and some decorations inside the tank but make sure that you are providing them enough space to swim freely.

The light inside their natural habitat is dim, meaning that light rarely reaches the middle and bottom layer where they are found. That is why they use the barbles to sense the obstructions. So, you should use dim lights. You should use an active water filtration system that can filter the entire tank within an hour. This will help provide more oxygen to your fish and would keep them healthy.

Water Conditions

Apart from the similarities in the habitat, you will have to provide them similarities in the water conditions. These water conditions include pH, hardness, and temperature. These are very important parameters because they directly impact the health and well-being of your Glass Catfish.

  • pH: 6.5 to 7.5 Neutral is better
  • Hardness: 10 °dGH
  • Temperature: 25 °C (77 °F).

If you fail to maintain these parameters, it would impact the health of your fish. For example, any sudden changes in the temperature of your aquarium can kill the Glass Catfish because it is a cold-blooded animal and needs water to control its internal temperature. If this temperature is not maintained, your fish would die immediately. That is why if you are living in a cold area, you may need to use the water heater to control the temperature of the water.

The pH of the water also impacts the health of the fish as it can alter the internal chemistry of the fish. For example, if the pH of the water is below 6.5 it can lead to serious illness and even organ failure in the fish. Apart from pH, hardness is also important. The hardness of the water is the calculator of mineral content inside the water. If the mineral content is higher, it can kill the fish. That is why it is important to maintain these parameters inside the tank and protect your fish.

Water Source

For the Glass Catfish tank, you can use any type of water from any source. But you will have to filter that water to make sure that it is clean and does not contain any contaminants. Apart from that, filtration will also help you adjust the level of minerals inside the water. So, as long as you use the filtration process, you can use water from any source including nearby rivers, lakes, and also from your tap. Filtration not only prevents diseases but also helps you control the chemical composition of the water inside your tank.

Ideal Size For The Tank

There are multiple sizes of tanks that you can use for the Glass Catfish. The smallest size of the tank that you can use is the 20-gallon tank. A 20-gallon tank would support the 4 to 5 specimens inside the tank. But for a large population of Glass Catfish, it is recommended to use a 30-gallon capacity tank.

A large tank with more capacity will not only hold more fish but would also impact the health of your fish inside the tank. They will have more space to swim and explore. If you are building a community aquarium, you will have to use an even larger tank that can support the number of fish that you would put inside the tank. Use the standard fish/gallons ratio to calculate the ideal size for the tank of Glass Catfish.

Behavior and Temperament

The Glass Catfish is a passive-active fish species, meaning that it would swim slowly if it is alone but if it is paired with a school of other Glass Catfish, it would become an active fish species. It is also known for being peaceful and shy. Meaning that it does not intimidate other fish and would just peacefully swim. If it is attacked or intimidated, it would run and hide in the vegetation.

It swims near the middle layer instead of the bottom layer like most of the other Catfishes. Also, it is known for being a social fish species that accepts the new members of the tank very well and can get along with a large number of fish species as long as the other fish is also peaceful. You will also notice the schooling and shoaling behavior if you put an appropriate number of fish inside the same tank.

Breeding Glass Catfish

The Glass Catfish is one of those fish species that are very hard to breed in captivity. Especially if you are a new breeder, you might not be able to successfully breed them. Some expert breeders have had success at breeding them in captivity but that too required a lot of input. So, if you want to breed them, you should know that it would require a lot of hard work and effort and you should be ready for it beforehand.

Start by creating a separate breeding tank where you would breed them. Make sure that the breeding tank has similar conditions. You will need to lower the temperature to induce the spawning and breeding season’s condition. After that, put the male and a female in a separate tank. You may also use the showering of water in their tank to induce the rainy environment. This works because they breed and spawn during the rainy season.

You may notice that the male Glass Catfish and female Glass Catfish have started to circle each other. They might also fuse the barbels, if you see this behavior, you should know that it is a sign of success at breeding them. Females would lay eggs and scatter them in different places in the tank. Male Glass Catfish would go and fertilize each of these eggs.

Eggs and Fry Care

After that, eggs will take a few days to hatch. Once they hatch, small Fry would come out of these eggs and would start to eat the egg sacs. After that, they will be able to swim and that is the time you will have to start adding appropriate food for them inside the tank. There are a lot of different Fry foods available that you can use. You should feed them high protein foods so that they can grow. Brine shrimp is one of the examples of foods that you can feed to your fry. Fry can be introduced back into the original tank after a few weeks.

Diet of Glass Catfish

The Glass Catfish is an omnivore species, meaning that it eats several food types including live invertebrates, shrimps, algae, and vegetables. This makes it easy for you to feed them as you will have multiple options of foods to feed them. You can feed them algae flakes, frozen meat, and live invertebrates such as blood worms, and shrimps of small size. You should make a diet chart for them so that you can provide the proper nourishment. Make sure that you provide them with enough food that they can eat within a few minutes. Overfeeding can cause pollution inside the tank.

Diseases of Glass Catfish

The Glass Catfish is immune to a lot of fish diseases and can survive them. But you will still have to look for a few diseases that are bad and can kill the Glass Catfish. Below is a list of those diseases that can kill the Glass Catfish.

  • Lice Disease: it is a Parasitic infection that can kill your fish. It happens when the water is contaminated. This is a highly transmissible disease that is why you should create a hospital tank and treat your fish in that tank. Also, clean the entire tank before putting the fish back inside the tank.
  • Fungal Infection: It is characterized by the white patches on the body of the fish. As these are transparent fish, you would notice these spots easily. It is also a treatable disease but would require quarantine to protect the other members.
  • Ich: It is also a common illness characterized by white sand like grainy rashes on the body. This is a serious problem as it can not only kill the infected fish but can be transmitted from one member to the entire tank. So, quarantine should be the priority. After that, start treatment and give it prescribed medicines.
  • Dropsy: This is a disease that is characterized by protruding and bloating of the fish. You would notice that the fish body has started to swell. It is caused by water pollution and unfavorable conditions. So, if you see these signs, you should clean your entire tank and disinfect it before putting the fish back.
  • Fin Rot: This is an infection on the fins of the fish that can progress. It can cause the rot of the fins that can limit the swimming abilities of the fish. It can be treated using medicines.

Almost all of these diseases have something to do with the water parameters and cleanliness inside the tank. If the water is not clean, the chances of your fish becoming ill and spread of disease would be higher. So, it is very important to maintain the parameters as they will help you keep your fish healthy.

Are Glass Catfishes a Saltwater or Freshwater Species?

Yes, the Glass Catfish are a freshwater species. It lives in the basins of rivers near Thailand and Malaysia in East Asia.

Are Glass Catfishes a schooling species or not?

Yes, the Glass Catfish is a schooling fish species. The minimum number of individuals required to complete a school is 6. So, if you put the 6 Glass Catfish inside one tank, they would display the schooling and shoaling behavior. It would make your tank look alive and beautiful.

Conclusion – Are Glass Catfishes Suitable For Your Aquarium?

Well, it depends on your choice. If you like the beautiful fish and want a unique and transparent-looking fish in your tank. Then yes it is a suitable fish species for your aquarium. It will provide beauty and life to your aquariums. It is one of the most peaceful fish species that displays schooling behavior. That means, it would not swim alone but within a group and you will be able to enjoy a show of synchronized swimming. Although, it is not the best species for the new fishkeepers because it requires a lot of extra care. But still, if you want to learn about fishkeeping then it would be one of the best species that you can select for your aquarium.


Question: How big do glass catfish get?

Answer: The Glass Catfish can grow up to 5 inches. But most of them only reach three to four inches. The specimens that reach 5 inches are rare inside the aquarium. But if you take proper care and provide them with enough food, they can reach the 5-inch limit.

Question: Can glass catfish live alone?

Answer: No, the Glass Catfish does not like to live alone. If you kept one alone, it would develop anxiety and depression and would die within a few months.

Question: What is the lifespan of Glass Catfish?

Answer: This depends on the type of care you are providing. In their natural habitat, they can live for more than 8 years. But inside the aquarium, they rarely reach the 7 to 8 years limit because changes in water conditions impact their health and can kill them prematurely. So, if you want your fish to live up to 8 years, make sure that you control all the parameters correctly.

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