15 Fin-tastic Facts About The Threadfin Rainbowfish For Kids

Threadfin Rainbowfish facts about the featherfin rainbowfish

The Threadfin Rainbowfish (Iriatherina werneri), also known as Featherfin Rainbowfish, is a rainbowfish that is the only species that belongs to the genus Iriatherina in vegetation. The fish is characterized by its fins that are long and beautiful and is the most attractive fish among the other rainbowfishes. Threadfin Rainbowfishes are found in tropical northern Australia and New Guinea. Iriatherina werneri are peaceful fishes in the aquarium and they prefer to live in a group of six or more. To take care of their health, Threadfin Rainbowfishes should be fed an omnivore's diet of flake foods, brine shrimp, small live foods, and prepared foods.

Here are some interesting facts about the Featherfin Rainbowfish for your perusal. Afterward, do check our other articles on sockeye salmon and anchovies as well.

Threadfin Rainbowfish

Fact File

What do they prey on?

Mosquito larvae, brine shrimp

What do they eat?


Average litter size?

Up to 200 eggs

How much do they weigh?


How long are they?


How tall are they?

1.9-2 in (4.8-5.1 cm)

What do they look like?

Gray-green, yellow, red and blue color skin with elongated pelvic, and anal fins

Skin Type


What are their main threats?

Overfishing, large fish

What is their conservation status?

Not Extinct

Where you'll find them

Freshwater swamps, vegetated areas, and rivers


Indonesia, New Guinea, and Northern Australia





Scientific Name

Iriatherina werneri





Threadfin Rainbowfish Interesting Facts

What type of animal is Threadfin Rainbowfish?

The Threadfin Rainbowfish (Iriatherina werneri) is a type of fish that is characterized by its fins which are long and beautiful. This fish species lives in freshwater swamps and prefers to live in a group of six or more. These fish species are known to be attractive fishes among the other rainbowfishes.

What class of animal do Threadfin Rainbowfish belong to?

The Featherfin Rainbowfish (Iriatherina werneri) belongs to the class of ray-finned fishes as their fins are webs of the skin that are supported by bony or horny spines.

How many Threadfin Rainbowfish are there in the world?

There is no accurate and exact number stating how many Featherfin Rainbowfish (Iriatherina werneri) are there in the vegetation where they live.

Where does Threadfin Rainbowfish live?

The Threadfin Rainbowfish (Iriatherina werneri) prefers to live in freshwater swamps, demersal or thickly vegetated areas of flowing waters, and a planted aquarium in tropical northern Australia and New Guinea. Popular Threadfin Rainbowfish spots for their habitat are Indonesia, Northern Australia, and the islands of New Guinea. The Threadfin Rainbowfish also lives in the aquarium and should be handled with proper care.

What is a Threadfin Rainbowfish's habitat?

The Threadfin Rainbowfish (Iriatherina werneri) habitat includes freshwater swamps, demersal or thickly vegetated areas of flowing waters, and also planted aquariums or well-planted tanks.

Who do Threadfin Rainbowfish live with?

The Threadfin Rainbowfish (Iriatherina werneri) prefers to live in a group of six or more with the other companions. As the fish has long fins, this fish species should be kept in a tank without fin-nippers. These can include other species such as tetras, rasboras, cichlids, and danios.

How long do Threadfin Rainbowfish live?

The lifespan of a Threadfin Rainbowfish (Iriatherina werneri) is very little. This fish species lives up to four years. This species can live up to three to five years when the fish are kept in a well-maintained aquarium with proper care and food. The lifespan of the Featherfin Rainbowfish (Iriatherina werneri) is determined by certain factors such as climate change, eating habits, food, and other factors.

How do they reproduce?

The Featherfin Rainbowfish (Iriatherina werneri) breeding takes place the most successfully when these fish species are kept in tanks without any other fin-nipper species. The male Threadfin Rainbowfish courts the female Threadfin Rainbowfish by posturing in front of her by repeatedly quickly raising and then lowering the dorsal fin. After the mating is done, the female lays up to a clutch of 200 eggs.

What is their conservation status?

The conservation status of Threadfin Rainbowfish care is Not Extinct. The number of Threadfin Rainbowfishes increases or declines based on different factors which determine the number of the fishes.

Threadfin Rainbowfish Fun Facts

What do Threadfin Rainbowfish look like?

The Threadfin Rainbow fish is very tiny in size and has different colors such as gray-green, yellow, red, and blue, with bright colors which extend up to its fins. The fish has fins that are long and beautiful and grows up to 2 in (5.1 cm) long. The male Threadfin Rainbow Fishes have more intense colors.

The males of this fish species have more intense colors than the females.

How cute are they?

The Threadfin Rainbow Fishes are very cute as the aquatic adults' first dorsal fins are very small in size and look very adorable because of their different colors. Threadfin Rainbow fish species are the most attractive fishes among the other rainbowfishes. Threadfin Rainbow fish species are known to be peaceful fishes.

How do they communicate?

The Threadfin Rainbow fish species communicate by different gestures and motions.

How big is a Threadfin Rainbowfish?

The Threadfin Rainbowfish are very small in size and do not grow after a limit. The Threadfin Rainbowfish adult size can grow up to 2 in (5.1 cm) length and are very tiny creatures. They are half the length of clownfish.

How fast can a Threadfin Rainbowfish swim?

The Featherfin Rainbowfish are very sensitive to changes in water conditions and slow-moving. This fish lives in places that are less than 4.9 ft (1.5 m) in depth and are associated with floating lily pads.

How much does a Threadfin Rainbowfish weigh?

There is no accurate and exact information about how much a Threadfin Rainbowfish size and weight. The fish's weight varies depending on their size.

What are the male and female names of the species?

There is no specific name for the male and female Threadfin Rainbow fish. This peaceful fish is simply called male Threadfin Rainbowfish and female Threadfin Rainbowfish as there is no specific name for them. Determining the sex of the fish is easy based on their fins. The males have larger fins as compared to females.

What would you call a baby Threadfin Rainbowfish?

There is no specific or assigned name for a baby Threadfin Rainbowfish. The baby Threadfin Rainbowfish takes five to six months to grow into a fully grown Threadfin Rainbowfish of 2 in (5 cm) size in the aquarium.

Do humans eat them?

Yes, humans eat adult Threadfin Rainbow fish and use different food recipes for them. You must make sure that the Threadfin Rainbowfish for sale is bought from a reputable seller so that it is safe to eat.

Are they dangerous?

No, this fish is not dangerous. As per the description of this fish by Meinken in 1974, it is a very peaceful fish when kept in a tank and does not cause any major harm to the other species of fish.

Would they make a good pet?

Yes, these peaceful fishes do make good pets when they are kept in an aquarium with a group of six or more Threadfin Rainbow Fishes. With proper water conditions, stable water chemistry (pH between 6-7), regular water changes, and high-quality food, these fishes make a good addition to your aquarium. They must be fed an omnivorous diet of flake foods, brine shrimp, small live aquatic foods, and prepared foods. Proper knowledge of feeding and water quality required is also essential before you purchase this fish.

Did you know...

If the Threadfin Rainbow Fishes are feeling uncomfortable, sick, or competitive, their colors can deepen.

The fishes enjoy socializing with others but also need peace at the same time.

The color of the Threadfin Rainbow Fishes enhances with age.

How do Threadfin Rainbowfish breed?

The spawning of the Threadfin Rainbowfish is not at all difficult in the right conditions, though it becomes difficult to get the eggs to hatch and even more tough to keep the fry alive. A pair of matured males and females should be selected and then introduced to the breeding tank and then should be given food. The pair should be given either java moss or a spawning mop. Then the parents spawn for a few days in batches and then eggs are removed with the spawning medium as they are laid.

What to feed Threadfin Rainbowfish

The Threadfin Rainbowfish are omnivores and have small throats to feed. They feed on diatoms, unicellular planktonic algae, and small insects that are present in their natural habitat.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fish from our white tuna facts and warmouth fun facts pages.

You can even occupy yourself at home by coloring in one of our free printable yellowfin tuna coloring pages.



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