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October 24, 2013
Lake goby mystichthys
Many people only pay attention to big fish, because, for example, a shark can swallow a person. However, large sizes do not always portend a threat, since even the smallest fish can bring much more dangerous problems.
Of course, while swimming in the sea it is impossible to see such small creatures, but you need to know about them. In the Philippines (Luzon Island), not far from the South China Sea and the Pacific Ocean, one of the smallest fish has settled - the lake goby mystichthys. In addition, lagoons, estuaries, estuaries and mangroves are considered suitable places. The length of this tiny male fish is only 1-1.5 centimeters, and the adult female reaches up to 14 centimeters. They are so transparent that they are practically invisible in the water, so there is little information about them due to the difficulties of catching. Alone, they never swim, mainly their habitual movements are based on grouping in large flocks. Basically, the process of catching occurs when the fish begin to spawn. At this time, namely monthly on the fourth day after the full moon, it is quite easy to catch them in large numbers. This is especially important for the economic sphere of activity of the northwestern provinces of these islands. Mistichthys is not dangerous to humans, besides, it is eaten by local residents. They catch it in dozens and prepare it according to special recipes. Since the goby is the smallest vertebrate in the world, dishes usually consist of a dozen fish. In addition to its usual habitat, mistichthys can be found in European waters. As for the Black and Azov Seas, there are Berg gobies. The length of such a small fish reaches approximately three centimeters. This goby is considered the smallest species of vertebrate animal class in Russia.
Baikal goby
In fresher sea waters, a large number of fish are found, the length of which barely reaches 5-10 centimeters. For example, a common Baikal goby - a stone sculpin - boasts a size of about 8 centimeters, and only occasionally some individuals can grow up to 14 centimeters. Basically, the habitual habitat of this fish is stone caves. Here for her the most comfortable conditions for feeding and reproduction.
Aral nine-spined stickleback
The smallest fish also accept stickleback in their ranks. A large number of this species is found in the lake, river or brackish coastal areas of the sea. The full name of this fish is the Aral nine-spined stickleback, the length of which barely reaches 5-6 centimeters. This species is so common in water bodies that it may well become a commercial fish. In addition to selling fresh goods, in Finland and other Baltic countries, fish are caught, and then fat is extracted during processing. This product is sold separately and is used in technical fields of activity, as well as for the production of flour for livestock and poultry feed.
pygmy gobies
The smallest fish of all representatives of this class are considered dwarf gobies Paedocypris Progenetica (dwarf pandaka). Habitual habitat is the Indo-Pacific region. Studies conducted in the late 70s of the 20th century showed that the length of this male fish is approximately 8.9 mm. The females were 0.1 mm longer. This type of fish can mainly be found in the peat swamps of Sumatra and Indonesia. The choice for this area is justified by the presence of high acidity, about 100 times higher than the normal level of rainwater. Previously, there was evidence that such acidity cannot provide adequate conditions for life and reproduction. However, during the study, interesting information was discovered. This level of acidity can guarantee a full life for many species of animals and plants. In addition, they are so unique that they attract special attention. The small size of the fish helps them a lot in survival. For example, due to this, they require little food for existence. The most useful and necessary food is plankton, which lies at the bottom of reservoirs. The length of the pygmy pandaka has shortened due to several factors. So, I had to deprive the brain of part of the bone protection. Females, on the other hand, have much fewer eggs than other types of fish. However, the prospect of survival for these dwarfs is not very good, since swamps are drained due to active human activity, and their habitat is destroyed. Due to such actions, the pygmy pandaka is on the verge of extinction.
In addition to the already mentioned fish, some types of herring, minnows, bleaks, tops, minnows and loaches can be attributed to the smallest individuals of this class.
An interesting fact is that the plucking was named because of the presence of sharp spines that are located near the eyes. Thanks to them, the fish can pinch quite painfully.
Not everyone has a place in the apartment for a large aquarium, but you really want to admire the underwater world. The way out of this situation can be the purchase of a small container. However, not all varieties of fish can be kept in a small aquarium.
Consider the most common types of fish for such aquariums.
What aquarium is called small?
Small aquariums include tanks less than 30–40 liters, they are also called nano aquariums. Most often they buy glass products from 5 to 20 liters. Now on sale there are aquarium sets, which include everything you need.
They are much cheaper than large aquariums, almost any stable surface is suitable for them, and care for such small volumes takes much less time. They like to have just on the desk. 
Even in such a small container, you can create a beautiful design using aquatic plants, snags, shells, stones and other elements.
Important! Due to small volumes, water indicators can change dramatically under the influence of external factors, which adversely affects its inhabitants and vegetation. Therefore, the parameters of nanoaquariums should be monitored and controlled using special equipment (filter, heater), and water should be changed in time.
The smallest aquarium fish
In small aquariums, they usually contain unpretentious small freshwater fish. Often only one species of fish is bred, but other aquatic inhabitants can be added to some species that are peaceful in nature. True, all such tenants should first be checked for compatibility.
It got its name because of the unusual shape of the jaw in males, which have processes that look like teeth. Elongated fangs are located on the lower jaw, which gives the fish a menacing look. In length, adult specimens reach 1 cm. Bones and internal organs are visible through the transparent body. 
In terms of feeding, danionella dracula are unpretentious, the main thing is that the food should also be of small parameters. Food can be given dry, in granules, freeze-dried, live, frozen, brine shrimp are well suited.
These peaceful fish love to swim in flocks, which number about 200 relatives, so they need to be kept in a group of at least 10 specimens.
Danionella dracula, due to its small parameters, is best kept in a species aquarium separately or with the same small fish. For them, an aquarium of 40 liters is recommended. The aquatic environment must comply with the following parameters: temperature - 20–26 °C, acidity - 6.5–7.5 pH, - 2-5dGH.
This well-known fish is also called the fiery tetra for its monochromatic orange color. Usually it reaches 1.5–2 cm, and males do not differ from females.
They are unpretentious to the conditions of detention, and can eat any food for fish of small fractions. They live in flocks, but a few pieces can be placed in a small aquarium, kept in the middle layers. 
They have a peaceful nature and get along well with other small peaceful fish. When designing an aquarium, live algae should be used, and lighting can be natural.
This small striped fish appeared relatively recently. Dark blue stripes from the back alternate with pale green, and the tail has a black spot. In males, the fins have a reddish tone.
It grows to an average of 2 cm and has a calm nature that allows it to be kept with other small peaceful fish, but is best kept separately. They prefer to swim in the middle layers of water.
It is perfectly acceptable to keep it in a 30 liter aquarium with small algae and feed it with various small fraction feeds. A family of one female and two males can be kept in a 15 liter tank where they will successfully breed. 
They love clean water, it is undesirable to put driftwood and tree leaves in their abode. They need good filtration and frequent water changes, temperature -
20–24 °С.
Did you know? Watching fish in an aquarium lowers blood pressure and heart rate. Such conclusions were made by scientists of the National Marine Aquarium together with researchers from the Universities of Exeter and Plymouth.
A little-known small striped fish, the males of which grow up to 2 cm, and the females up to 2.5 cm. This is a rare viviparous fish of the Pecilia family.
For a pair of neoheterandria elegans, a 12-liter aquarium is enough. They are omnivorous and can eat any small food, but live or frozen food is preferable.
They love clean soft water. They need filtration and a weekly change of half the water. Recommended temperature -
24–30 °С. It is permissible to keep them with other small tenants. 
It belongs to one of the smallest fish in the world. It is ideal for keeping in small aquariums with a volume of 10 to 15 liters. Experts recommend keeping a flock of Formoses (about 40-50 pieces) in an aquarium of 30-40 liters.
In smaller volumes, at least 10 individuals should be started. It should be noted that males should be about three times more. Formosa are not aggressive, get along with many fish and shrimps, but the best option for these fish is a separate species aquarium. They belong to viviparous fish and inhabit the upper and middle layers.
Inconspicuous in appearance: gray color with a dark stripe along the body, transparent small fins. Females are larger than males. Males are approximately 1.5 cm, while females reach 3.5 cm.
Formosa are useful in that they eat (small white worms) than produce a natural cleaning of the aquarium from these unwanted guests. In nature, they feed on small insects that fall into the water, which is why they prefer. 
Bloodworms, brine shrimp and tubifex are well suited as food. Forage is recommended to take small or pre-crushed. For formose, the optimum water temperature is 22-26 ° C, but they tolerate the range from 12 to 30 ° C quite normally.
It is desirable to have more aquatic plants in the aquarium. These fish do not need frequent water changes. It is better to cover the aquarium from above, as the fish can jump out of it.
Important! To prevent formoses or other fish from eating fry, the aquarium must have a lot of algae and enough food.
The males of these fish usually reach 2 cm and have a slightly more contrasting color, while the females grow up to 2.5 cm on average. When the tetradon is frightened, it swells like a ball and small spikes begin to be visible on the body.
In an aquarium with a capacity of 10 liters, 2-3 individuals can be kept. Their coloration is dominated by greenish-yellow tones with dark spots.
Their eyes move independently of each other. These are unpretentious fish, but they prefer live food, you can also give frozen food. 
Tetradons also need to be fed snails, on which they sharpen their teeth. These active fish are best kept separate from other species.
It is the smallest fish in the wedge-bellied family. In length, it reaches 2.2–2.5 cm. Like all members of this family, it has an unusual elongated body shape, which is flattened on the sides.
The line of the back is straight, and the abdomen is sharply curved in the form of an arc. A light, translucent body has an olive tint, and dark specks in the abdomen, a dark line runs along the spine.
Important! It should be noted that carnegiellas do not tolerate transportation well and after it they often get sick - they have white spots on their scales. If such stains are found, they must be moved to a separate container for quarantine, which will last 14–28 days until the disease has completely passed.
These shy fish are recommended to be kept in flocks of 5 or more. Parameters of the aquatic environment for optimal content: temperature -
23-26 °C, hardness -
pH 5.5–6.5, acidity -
dH 10-20. 
There should be constant water changes, aeration and filtration. Both dry and live food are suitable for nutrition. Carnegie pygmy eat from the water surface or middle layers. Food that falls to the bottom, they simply do not notice.
Dwarf corridor
This catfish grows only up to 2-3 cm long. It has a translucent laterally flattened body of golden yellow and olive tones with a dark spot, small antennae.
Females are slightly larger than males. Lives in a flock and gets along with other small inhabitants of the aquarium. A few things can be kept in small aquariums.
Keeps in the middle layers of water and loves to bask in the ground. It feeds on various small clods for fish. It needs a filter, aeration and a weekly change of a fifth of the water. 
One of the most unpretentious and interesting in appearance fish, perfect for beginners. This is a favorite fish for geneticists and breeders.
Now about 13 varieties of guppies have been bred, differing from each other in body size and tail shape: lyre-tailed, fan-tailed, veil-tailed, round-tailed, flag-tailed, needle-tailed, spade-tailed, spear-tailed, “lower sword”, “upper sword”, “double sword”, sharp-angled fan-tailed and fantail edged.
Coloring can also be very diverse. They usually swim in the upper layers of the aquarium. The length of males usually ranges from 1.5–4 cm, but females look inconspicuous and larger - up to 6 cm.
Due to its small size and unpretentiousness, a small group of guppies can be kept in small aquariums, even in a three-liter jar. If the plants in the aquarium are also undemanding to the conditions, then you can even refuse the filter and aeration. 
However, in any case, one should not forget about frequent water changes and cleaning the soil. They live well in the temperature range of 20-27 ° C and breed easily.
The small (2–3.5 cm) body of this aquarium fish has longitudinal stripes and a somewhat elongated body. In the dark, it changes its color, turns pale.
They are advised to keep in a flock of up to 10 pieces in an aquarium of 30-40 liters, but a small group can be kept in even smaller containers. They can get along with other peaceful small fish. They like the presence of lush aquatic vegetation and dark soil.
Unpretentious to feed, feeding only dry small feed is allowed, but you can replenish their diet with daphnia and brine shrimp. Filtration and weekly water changes are required.
They love the presence in the decor that saturate the water with tannins, subdued lighting, float in the upper and middle layers. 
Rasbora
A small unpretentious fish of the carp family, which is best kept in a flock. She is peaceful and very active. The sizes of fish of this species range from 1.3 to 10 cm. The following varieties of parsing are common among aquarists:
Rasboras breed easily, unpretentious to the conditions of detention. Feed can be used both dry and frozen, small fractions. In the place of residence there should be algae that serve as plant food for her. Keeps in the upper layers of water. Optimum content temperature -
24-26 ° C, regular replacement of a fifth of the water is necessary. A flock of these fish of 8-10 individuals is recommended to be kept in an aquarium from 50 liters, but a small aquarium is also suitable for a few pieces. Did you know? The smallest of the marine fish is the pygmy goby (Trimmatomnanus), which lives in the Indo-Pacific region. In length, males reach an average of 8.9 mm, and in females 9 mm.
Rules for settling small fish
When settling in a nanoaquarium, aquarists recommend adhering to the following rules:
Did you know? The world's smallest aquarium with inhabitants was created by Omsk miniaturist Anatoly Konenko together with his son. They placed soil in 10 ml of water and planted cladophora bushes, released fry. Such a small volume was serviced by a specially designed mini-compressor.
A small aquarium takes up little space, but is just as pleasing to the eye as a large one. It is easier to take care of it, but various sanitary and preventive measures (water changes, cleaning, disinfection, soil and plant changes) are carried out more often. It is important to correctly calculate the number of residents for such small containers. Beginners should choose the most unpretentious fish and slow-growing plants. But they will also need to constantly monitor the small capacity. But in such small volumes, you can easily change the scenery, plants and create a new design.
Aquarium launch: video
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Miniature fish can be seen not only in small aquariums, they live in fresh water, and also live in salty sea water. What is most surprising, many of them are commercial.
The smallest river fish Among the small and light freshwater fish is the mystichthys goby, whose habitat is the lakes and rivers of the Philippines. This is a commercial fish. The length of the fish is about twelve and a half millimeters. Fish live in small flocks. The local population prefers to use these gobies, making delicious dried cakes out of them.
The bobbin fish is found in Russian rivers and lakes. Its size is also small. So, the length of the Aral nine-spined bobbin is only five centimeters. There is so much of it in reservoirs that it may well be commercial. This subspecies of bobbin is caught in the Baltic States and Finland. The bobbin processing field produces fat, which is used for technical needs. Bone meal is also obtained for poultry and livestock feed.
The smallest marine fish Of all marine fish, the pygmy goby has the shortest body. Its habitat is the Indo-Pacific region. It is known that the body length of females is only nine millimeters, and males are a tenth of a millimeter less.
The pygmy goby was also accidentally discovered in the Shetland Islands, which was a real discovery. However, it was not so small in size - the maximum length was twenty-four millimeters. The name of the fish is Gillett's goby. This goby is considered the smallest marine fish in Europe. Due to their small size and mysterious color, thanks to which they easily hide among shell fragments, it is extremely difficult to thoroughly study this species. To date, it is only known for certain that their habitat is the rough seabed.
It is impossible not to say about another variety of goby that lives in the seas and is the smallest marine commercial fish - this is sinarapan. These fish live on the island of Luzon in the Philippines. The length of males does not exceed thirteen millimeters. Unfortunately, this species of goby is also on the verge of extinction.
In Russia, the smallest fish is the Caspian goby Berg. It belongs to the smallest subspecies of gobies. Its habitat is the bottom layers of the Caspian Sea. The length of such a fish usually does not exceed two centimeters. Sometimes it can be found in the lower reaches of the rivers flowing into the Caspian.
Small aquarium fish Usually small aquarium fish live in small aquariums installed in homes, shops or offices.
Here are some types of miniature aquarium fish. Rasbora Brigitte - this fish, even in wildlife, does not exceed two or three centimeters. Just as small are Rasbora Mera and Rasbora Spotted. The smallest of them is Rasbora Kroshka, whose length is no more than one and a half centimeters. No more than two centimeters - the size of the Rasbora Firefly fish.
In miniature aquariums, the dwarf Tetradon can often be seen. The male grows up to two and a half centimeters. The females are slightly larger. Small Pygmy catfish live in flocks in aquariums. The length of these fish is about two and a half centimeters. Another small schooling fish is the Microrasbora Galaxy. Its size is two and a half centimeters.
The nano-aquarium was created by Anatoly Konenko, a resident of the city of Omsk. Its volume is only two teaspoons of water. It is active, and fish live in it. Its inhabitants are zebrafish fry, the length of which is only four millimeters.
The smallest fish in the world The smallest representative of the class of mystichthys gobies is the pygmy pandaki. The place of its discovery is the swamp of the Indonesian island of Sumatra.
The weight of this "baby" is about four to five grams, and the length is about seven to nine millimeters. In the water, the fish are barely visible not only because of their size, but also because they are almost transparent and colorless. Pandaks are not only the smallest freshwater fish on the planet, they are also the smallest vertebrate in the world.
Their usual habitat is the Indo-Pacific region. Often these dwarf fish are found in the peat bogs of Indonesia and Sumatra. The choice of location is not accidental, the reason is the increased acidity, which exceeds the acidity of rainwater by a hundred times. In the seventies of the last century, studies of pandaks were carried out, which led to interesting discoveries. Due to their small size, the fish require little food. They feed on plankton at the bottom of water bodies. The small length of the fish and the small weight are justified by the fact that its brain is deprived of part of the bone protection, females have much fewer eggs compared to other fish. There are so few eggs that the male is able to fertilize each of them individually.
The locals, despite the small size of the fish, eat them fried with many spices. Raba is also of interest to aquarists.
Pandaks have long been on the verge of extinction. The reason is in the activities of a person who continues to drain the swamps and thus destroys the habitual and natural habitats of these small fish.
But the largest fish in the world grow in length more than 20 m.
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The smallest fish in the world is the pygmy pandaki. They are not only the smallest freshwater fish on the planet, they are also the smallest vertebrate in the world. Their usual habitat is the Indo-Pacific region. Often these dwarf fish are found in the peat bogs of Indonesia and Sumatra.
Miniature fish can be seen not only in small aquariums, they live in fresh water, and also live in salty sea water. What is most surprising, many of them are commercial.
The smallest river fish
Among the small and light freshwater fish is the goby mystichthys, whose habitat is the lakes and rivers of the Philippines. This is a commercial fish. The length of the fish is about twelve and a half millimeters. Fish live in small flocks. The local population prefers to use these gobies, making delicious dried cakes out of them.
Mistichthys - small freshwater fish
The bobbin fish is found in Russian rivers and lakes. Its size is also small. So, the length of the Aral nine-spined bobbin is only five centimeters. There is so much of it in reservoirs that it may well be commercial. This subspecies of bobbin is caught in the Baltic States and Finland. The bobbin processing field produces fat, which is used for technical needs. They also produce bone meal for poultry and livestock feed.
The smallest sea fish
Of all marine fish, the pygmy goby has the shortest body. Its habitat is the Indo-Pacific region. It is known that the body length of females is only nine millimeters, and males are a tenth of a millimeter less.
Dwarf goby - fish with the shortest body
The pygmy goby was also accidentally discovered in the Shetland Islands, which was a real discovery. However, it was not so small in size - the maximum length was twenty-four millimeters. The name of the fish is Gillett's goby. This goby is considered the smallest marine fish in Europe. Due to their small size and mysterious color, thanks to which they easily hide among shell fragments, it is extremely difficult to thoroughly study this species. To date, it is only known for certain that their habitat is the rough seabed.
It is impossible not to say about another variety of goby that lives in the seas and is the smallest marine commercial fish - this is sinarapan. These fish live on the island of Luzon in the Philippines. The length of males does not exceed thirteen millimeters. Unfortunately, this species of goby is also on the verge of extinction.
Sinarapan - the smallest commercial fish
In Russia, the smallest fish is the Caspian goby Berg. It belongs to the smallest subspecies of gobies. Its habitat is the bottom layers of the Caspian Sea. The length of such a fish usually does not exceed two centimeters. Sometimes it can be found in the lower reaches of the rivers flowing into the Caspian.
small aquarium fish
Usually small aquarium fish live in small aquariums installed in homes, shops or offices.
Small aquarium for small fish
Here are some types of miniature aquarium fish. Rasbora Brigitte - this fish, even in wildlife, does not exceed two or three centimeters. Just as small are Rasbora Mera and Rasbora Spotted. The smallest of them is Rasbora Kroshka, whose length is no more than one and a half centimeters. No more than two centimeters - the size of the Rasbora Firefly fish.
In miniature aquariums, the dwarf Tetradon can often be seen. The male grows up to two and a half centimeters. The females are slightly larger. Small Pygmy catfish live in flocks in aquariums. The length of these fish is about two and a half centimeters. Another small schooling fish is the Microrasbora Galaxy. Its size is two and a half centimeters.
Microrasbora Galaxy - an aquarium fish with a size of only 2.5 mm
The nano-aquarium was created by Anatoly Konenko, a resident of the city of Omsk. Its volume is only two teaspoons of water. It is active, and fish live in it. Its inhabitants are zebrafish fry, whose length is only four millimeters.
The smallest fish in the world
The smallest member of the mystichthys goby class is the pygmy pandaki. The place of its discovery is the swamp of the Indonesian island of Sumatra.
A delicacy from the smallest fish in the world
The weight of this "baby" is about four to five grams, and the length is about seven to nine millimeters. In the water, the fish are barely visible not only because of their size, but also because they are almost transparent and colorless. Pandaks are not only the smallest freshwater fish on the planet, they are also the smallest vertebrate in the world.
Their usual habitat is the Indo-Pacific region. Often these dwarf fish are found in the peat bogs of Indonesia and Sumatra. The choice of location is not accidental, the reason is the increased acidity, which exceeds the acidity of rainwater by a hundred times. In the seventies of the last century, studies of pandaks were carried out, which led to interesting discoveries.
Here is the smallest fish
Due to their small size, the fish require little food. They feed on plankton at the bottom of water bodies. The small length of the fish and the small weight are justified by the fact that its brain is deprived of part of the bone protection, females have much fewer eggs compared to other fish. There are so few eggs that the male is able to fertilize each of them individually.
The locals, despite the small size of the fish, eat them fried with many spices. Raba is also of interest to aquarists.
Mistichthys not only eat, but bred in aquariums
Pandaks have long been on the verge of extinction. The reason is in the activities of a person who continues to drain the swamps and thus destroys the habitual and natural habitats of these small fish.
Small fish living in the seas and oceans are not so rare. Some of their species can be seen in home aquariums of exotic lovers. You will not believe, but most of them are commercial, and are actively caught by man. These tiny creatures live in both salt and fresh water.
The smallest representative of freshwater fish is mystichthys which belongs to the goby family. The homeland of this dwarf fish is the Philippines. The goby lives in freshwater rivers. The length of his body does not exceed twelve millimeters. The goby is kept in small flocks, consisting of several hundred individuals. Mystichthys is very popular among the local population. The fish is dried and used to prepare various dishes that are very popular among tourists.
In Russian freshwater rivers, one can meet another representative of dwarf fish of commercial importance. it stickleback- a miniature fish, no more than five centimeters long. Technical fat is obtained from it, as well as fishmeal rich in vitamins, which is used in the manufacture of feed for birds and animals.
Dwarf fish can also be found in the sea. Among them, for example, are pygmy goby found in the Indian and Pacific oceans. The length of the fish is not more than nine millimeters. She has an original color, thanks to which she is completely invisible on the seabed, covered with shells. Among them, the goby is hiding. For ichthyologists, it remains a mystery to this day. In addition, this dwarf fish lives at a rather great depth, which makes it difficult to study it.
The smallest marine fish of commercial importance is sinarapan. It lives in the coastal waters of the Philippine island of Luzon. The length of her body is not more than thirteen millimeters. Today, the Sinarapan population is at a critical level, so its fishing is prohibited.
A dwarf fish also lives in the Caspian Sea. it Caspian goby. The length of his body is not more than two centimeters. The goby leads a benthic lifestyle, but sometimes enters the lower reaches of freshwater rivers.
Scientists agree that the smallest fish in the world is goby pygmy pandaki. It was found in a swamp, which is located on the island of Sumatra. This baby weighs four grams, and the length of her body is only seven millimeters. The body of the pandaka is absolutely transparent, so it is invisible in the water. The fact that the fish prefers the swamp is easily explained. In such reservoirs, the water has an increased acidity, which is important for its normal existence. The size of the fish is small, it consumes little food. This is mainly benthic plankton. Due to such a small size, the female can lay only a few eggs, each of which is fertilized by the male individually. Locals catch pandaks and eat them.
And yet, the smallest fish are kept by aquarists. They are tiny, colorful, with an original body shape. There are a lot of types of aquarium dwarf fish. The most popular are: Rasbora Brigid, Rasbora Measure, Rasbora Spotted, Rasbora Kroshka. The fish are tiny. For example, the body length of the same Crumb is no more than 15 millimeters. Rasbora Firefly grows no more than 20 millimeters.
Also in home aquariums you can see Tetradon, whose length is not more than 25 millimeters. There are quite a lot of small aquarium fish. These are the same dwarf catfish, zebrafish, pandaks, etc.
