Most Dangerous Aquarium Fish #15. Bucktoothed Tetra
Native to the Amazon Basin and Guyana. It is light tan in appearance/ with two distinct black spots/
and can grow up to 4.7 inches in length. The Bucktoothed Tetra is unsuitable for Aquariums/
because it is very aggressive/ and will attack any and every fish in the tank. Even if larger
fishes keep it at bay, it will descale and attack smaller fishes. They are also infamous for their
scale-eating habits, smashing their specialized teeth against larger fish at high speeds/ to knock
loose clouds of scales to eat. #14. Red-Tailed Black Shark
This is a species of freshwater fish in the carp family. It is endemic to Thailand/ and
critically endangered. However, due to its beautiful appearance, consisting of
a black body and a red tail, it is common in aquariums. It can grow up to 6 inches long.
In spite of their name, they aren t true sharks. However, being solitary, territorial
bottom dwellers, putting them in a tank with other fishes/ is a recipe for disaster. Unless
they are given a cave, they will claim the bottom part of the tank as their own, attacking anything
that descends. Because of their rarity and endangered status, they are expensive to buy.
#13. Black Piranha Also known as the Redeye Piranha,
this is a freshwater ray-finned fish common to the northern part of South America.
This fish averages a length of 13 inches, although certain individuals have been noted to grow up to
16.3 inches. They also commonly attain a maximum weight/ of about 6.6 pounds.
It is one of the larger species of piranha. Whatever the body color, this species always
has red eyes. They re especially dangerous, not just to fish but to their human handlers as well.
When they re done growing, they consider the entire tank as their territory. As such,
they will attack any invaders. They require expert care for maintenance.
#12. Ornate bichir The Ornate bichir is a truly
beautiful fish. Also called the dragon eel, it is a bony fish found in Lake Tanganyika/ and the
Congo River basin in Central and East Africa. It has black and yellow patterning on its body, head,
and fins, with 9 to 11 dorsal spines. It can also grow up to 24 inches in length.
The Ornate bichir is very aggressive, unlike other fish in its family. It may tolerate larger fish/
but tends to attack small, bottom-dwelling, or similar-looking species. They tend to go after
fishtails a lot. And so, if a fish has a damaged tail, the bichir is the most likely culprit.
#11. Severums Heros severus, also known as the Banded
Cichlid and the Severums, is a species of tropical freshwater cichlid native to the upper Orinoco and
upper Rio Negro basins in South America. It is often confused with other fishes of the same
family and is rarely used in the aquarium trade. It can grow up to 8 inches long.
They may look docile due to their colorful mouths and eyes; however, they are really aggressive/ and
will kill anything they can. They tend to do well with other cichlids of the same size. However,
they re not as merciful to other tankmates. #10. Arowana
This family of fish has a mosaic pattern of canals/ covering their scaled bodies.
Also known as bony tongues, they have a toothed bone on the floor of the mouth, equipped with
teeth that bite against teeth/ on the roof of the mouth. The arowana is a facultative air breather/
and can obtain oxygen from air by sucking it into its swim bladder, which is lined with capillaries
like lung tissue. They can grow up to 2 feet long, although this depends on the species.
They are a staple fish in aquariums worldwide/ and can come in a variety of colors.
Some of these colors are really rare/ and can cost as much as 100,000 dollars.
What makes them dangerous is that they are highly active top-dwelling predators.
#9. Jack Dempsey This freshwater fish is named after the famous
1920s boxer Jack Dempsey. The name arises due to the fish s strong facial features and aggressive
nature, just like the boxer. It is a freshwater fish native to Mexico and Honduras. It prefers
water with a neutral pH range and a temperature between 72- and 86-degrees Fahrenheit. They can
grow up to 10 inches in length/ and tend to eat worms, crustaceans, insects, and other fish.
It is a widely popular aquarium fish due to its iridescent scales. To keep them in check,
they can only share a tank with large, similarly aggressive cichlids. They also need
caves to keep them calm. #8. Pea Buffer
The Pea Buffer fish/ is also known as the Dwarf or Pygmy Pufferfish. It is a small freshwater
pufferfish endemic to the Kerala and southern Karnataka regions of Southwest India. Due to
loss of habitat and overfishing for the aquarium trade, natural populations are threatened.
The maximum size of this fish ever noted is 1.4 inches. In spite of their small size,
they can take out much larger fish. These fish are very territorial, and if they can t kill
another fish outright, they will take out chunks of it until it dies a slow, painful death.
#7. Tiger Barb The Tiger Barb or Sumatra Barb
is a tropical cyprinid fish that can be found mostly in Indonesia. However,
they can be found in other parts of Asia as well. They can grow up to 3.9 inches long and 1.6 inches
wide. All species of this fish are quite colorful, which is why they are coveted for aquariums.
They are very aggressive/ and tend to nibble on the fins of other smaller or more passive species.
However, their aggression tends to fall when they are housed with members of the same species.
In such situations, they form a shoal that can produce a stunning show through the tank.
#6. Gourami These are a group of freshwater anabantiform
fishes that are native to India, Pakistan, and Korea. They tend to have an elongated,
feeler-like ray at the front of each of their pelvic fins. With 133 species,
they tend to grow as long as 5 to 6 inches. Although they are aggressive, these Gourami fish
tend to co-exist peacefully with fishes of other families. However, when they are kept
with fishes of the same family, they tend to act out. This is the opposite scenario for most
other fishes. They are personable and intelligent and tend to do a good job of distinguishing
between their tank mates. #5. Flowerhorn Cichlid
This fish s most distinguishing feature, other than its vivid coloration, is its bulging
forehead, which is colloquially called a Kok. They are a man made hybrid/ that exists in nature
only because of intentional release by man. They can typically be found in Singapore and Malaysia/
and are classified as an invasive pest species. Their importation is banned in Australia.
They have a lifespan between 10 to 12 years/ and can grow up to 14 inches long. Although
they are very playful/ and tend to interact with humans and sometimes put on a show,
they can be very aggressive as well. Being aggressive and territorial, two or more
flowerhorns/ are usually not kept together, but the tank housing them can be divided up with
acrylic dividers or egg crates. #4. Poor Man s Tropheus
A species of fish in the cichlid family that can grow up to five inches long.
It is native to South America, and its diet consists of algae and plant material/ which it
scrapes from rocks and other hard surfaces. They are so aggressive/ that they are sometimes used
for the cleaning of other fish parasites. They tend to kill fish larger than themselves.
Although some breeders have found success housing them with other fishes,
it s best to keep them in a tank/ all on their own. They tend to become territorial over caves,
and so if a special region is created for them, their aggressiveness is lessened.
#3. Afer Knife Also known as the reticulated knifefish,
it is a species of freshwater fish found in tropical West Africa. It reaches a maximum length
of 31 inches/ and can weigh as much as 2.9 pounds. Its dorsal fin projects out of its back/ like a
feather. It is laterally flattened/ and is capable of breathing air at the surface of water in
addition to normal breathing with its gills. The Afer knife tends to grow more aggressive as
it matures. At full size, they either need to be kept alone/ or with other large and
aggressive fish. They tend to dislike specific individuals/ rather than specific groups.
#2. Mini Dovii The Mini Dovii is sometimes
called the Many-pointed cichlid. They are native to Central America, in the waterways from Mexico
to Guatemala. They can live as long as ten years. They are kept in aquariums/ because they are quite
gorgeous and personable. However, they are also known for being aggressive and territorial.
The Mini Dovii only grows up to 10 inches, about half the size of a regular Dovii. They
tend to prefer waters in the neutral to slightly alkaline pH ranges. They prefer the bottom levels
of the tank/ and require intermediate levels of care. Going back to their aggressive nature,
these fishes are best kept in pairs. Otherwise, they kill everything else in the tank with them/
if they can. #1. Oscar Fish
Known also as the Tiger Oscar, the Velvet cichlid, and Marble cichlid, is commonly found in Tropical
South America. It is a popular aquarium fish in the US and Europe. It can grow up to 18 inches in
length and can weigh up to 3.5 pounds. Juvenile Oscars have a different coloration from adults,
and are striped with white and orange wavy bands, and have spotted heads.
They are very territorial and tend to do well with larger fishes of the same family.
Even so, they tend to bond with their human owners and interact with them a lot. It is recommended
that they be housed alone if possible. Would you rather spend $100.000 on a fish for
your aquarium/ or the same amount on a big shopping spree?