Redtail catfish: Lifespan, feeding, growth and diseases

Redtail catfish has large colorful catfishes have a brownish back, with yellow sides and characteristic orange-red dorsal finish and caudal finish (hence the common name).

This has on the upper jaw a pair of barbels and on the lower jaw two pairs.

Redtail Catfish In the Aquarium

The redtail catfish is an extremely popular fish in public aquarium Amazonian themed exhibits, in which they are often housed with other large fish such as Colossoma macropomum or pacu, and other large catfish. 

Despite its eventual large size, juveniles are often available as aquarium fish. These fish can grow quite quickly in an aquarium where they can be well-fed and require tanks of at least 10,000 l (2,600 US gal) when they are fully adults.

Redtail catfish in aquarium
Image by Mathias Appel from Flickr

This catfish is suitable for weekly feeding; overfeeding is a common cause of death in this species. so this is why, never over feed your redtail catfish.

It feeds extensively on dead and living fish and other meat. Even as a young man of only a few inches in length, they can swallow many of the most common aquarium fish such as tetras, mollies and it is only appropriate to house this fish with other relatively large species.

Redtail catfish are also used to swallowing inedible objects within the aquarium. Although these are frequently regurgitated, both swallowing and regurgitation can pose a problem for the fish and these objects are best kept out of the aquarium.

The redtail catfish were hybridized with other fish such as the Pseudoplatystoma sp tiger shovelnose. Tiger redtail catfish by the use of hormones in attempts to create a viable food fish.

Sometimes, these hybrid fish make it into the aquarium hobby under various common names.


Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Pimelodidae
Genus: Phractocephalus
P. hemioliopterus
Binomial name
Phractocephalus hemioliopterus

The redtail catfish, Phractocephalus hemioliopterus is a catfish which is pimelodid (long whisked). It is known as cajaro in Venezuela, and is known as pirarara in Brazil.

It is the Phractocephalus genus’ only remaining species. This fish is common in aquarium trade although it is unsuitable for all but the largest aquariums due to its massive adult size.

About Redtail catfish

The Redtail Catfish belongs to the Phractocephalus genus and is the only remaining known species. 

It also is known as that of the flat-nosed catfish, RTCs, catfish antenna, and catfish banana. 

It originated from the rivers of South America and the Amazon and can be found in Brazil, Peru, Venezuela, Colombia and other neighboring states. 

They have a long lifespan and if properly cared for, they can live in excess of 15 years. 

While they begin quite small in size (around 5 cm), they grow rapidly too big for the tanks of most aquarists, and are often donated to public aquariums.

However, with the frequency at which this occurs, it is difficult to find a zoo or aquarium which will accept large fish kept private. 

So, before we go on, if you’re uncertain about being able to take care of a fish of this size for the duration of its life, we recommend avoiding this fish.

Redtail Catfish Appearance

redtail catfish appearance
Image by Serstef from Wikimedia commons

Redtail Catfish are colourful and large. They’ve got long whiskers (i.e. barbels) on their mouths, and a nice red tail. 

They are mostly dark gray / brown along their body’s top side with small dark spots scattered around them, and a pale yellow / white white wavy band stretching both sides of their body. 

It has a cylindrical shaped body, with the a flat belly and a compressed tail laterally. 

A red-orange color is the top of the dorsal and caudal fin, with three pairs of long barbels; two on the lower jaw, and one on the upper jaw.

Check this article on oscar fish

Redtail catfish size and growth

The redtail catfish size and growth when imported into pet stores, juveniles are usually about 5 cm long. 

Your pet-store might have told you that this fish only grows 12 inches in your aquarium. That’s not quite true.

The myth that a fish will only grow to the size of its tank is among the aquarist hobby a truly dangerous one. 

When they’re young, these fish can easily grow one inch a week; most reach two feet within a year. 

In home aquariums, they can reach lengths of more than 4 feet, and left in nature, growing even larger. 

The largest recorded Redtail Catfish was found in the Amazon River in 2010, having a length of 63 inches and weighing 123 lbs.

Redtail catfish Feeding

Redtail Catfish are not challenging eaterers. They’ll actually eat anything that fits into their mouth. 

They are omnivorous, but they prefer a meaty diet. Ideally, the diet of the RTC should consist of sinking pellets of carnivore, cutting fish and meat, shrimp, crayfish and worms.

You might also want to make your own meals to make sure they get the best possible diet. 

While you’ve probably seen live feeding videos on Youtube, it’s not required. Feeders are often grown under inappropriate and crowded conditions that lead to many problems, one of which is that they have little, to no nutritional value.

They could also carry disease and infecting parasites. In addition, live feeders are expensive compared to healthier alternatives and more nutritional ones. 

Overfeeding is a common problem among these species. 

After each feed, these fish become very sluggish, and take time to properly digest their food. Young people should be fed every other day, but they will only require one large meal per week as they mature. 

Once you come to know your fish, when they’re sluggish, you can watch for signs. When they become active again, you will notice, and you will find out when to feed them. 

They may be trained to take food from the hands of their owner.

Redtail catfish tank mates

A juvenile catfish could be very timid. Some suggestions to help them overcome their shyness include: providing them with cave areas to hide in (make sure they ‘re not small enough to eat) and keeping the tank in an area where you’re spending plenty of time to use them to interact with yourself. 

Ideally you should just house Redtail Catfish alone. 

If you really do want a tank mate, make sure you can’t fit into their mouth whatever you put in like that. 

They can easily eat anything that is half their size, and even eat things that are greater than half their size – this can be fatal as they choke.

RTC’s are natural predators, and they will attack and eat smaller fish, so that any fish smaller than them are not suitable mates of the tank. 

Tank mates should be similar in size; suitable fish should include: Gars, Stingrays, and Datnoids. Housing them all together from a young age, too, is best. 

You can house RTC’s together, the chances of them breeding in a home aquarium are very low, but you should also know that at the juvenile stage there are no distinctive features to determine their sex.

Check out this article on Pictus Catfish

Tank requirement

If there is only one piece of advice to give about the tank – buy the fish only when you’ve got a huge tank. Don’t buy one; think in a year or two you’ll buy a larger tank, because very rarely will people. 

A lot of debate is going on around the size of an acceptable tank for this species. 

We recommend as a bare minimum, this fish will need a 1000 gallon tank, which should be at least 12 x 4 x 3 feet, even for a fully grown RTC this size would not be suited.
Instead, many people decide on indoor ponds for this species which is a more suitable solution for housing.

We mentioned earlier that this species is going to eat literally anything that fits in its mouth, so they need very sparse tanks. Do not decorate your tank with gravel and loose parts. 

They’ll eat stones and gravel in terms of substratum so ideally you should have a bare bottom tank, but if you don’t really like the look of bare bottomed tanks you could use a layer of sand. Keep in mind that it is easier to clean a bare bottomed tank. 

They are fish that dwell in the middle to bottom and prefer low lighting. 

Redtail Catfish typically live in a tropical environment, so it needs to match their tank conditions. Their water should be kept between 20 and 26oC (68-79oF) in between.

If you are in a climate that regularly drops below those temperatures you will need a water heater. You should maintain as stable a temperature as possible. 

The pH should be around 6.0 to 7.5. 

Because of the tank ‘s size, you will find it almost impossible to find a traditional filter that will be effective so that the best option is a sump filter. 

Commercial sumps tend to be very expensive so if your budget does not allow a commercial sump, you might want to build your own.

should you keep a Red tail Catfish? 

There’s really just one question that you have to ask yourself to help decide if you want to keep an RTC. That is, can you give them the best life possible for the length of their lives? 

This includes a sufficiently large tank, preferably a pond, the commitment of time to feed and change the water, and being prepared for the fish research and care. 

If you’re committed to providing all of this with an RTC, and you like the thought of looking after such a huge fish, then a redtail catfish is a beautiful and unique fish to keep.

How long do redtail catfish get?

Redtail catfish can reach a length of about 1.8 m (5 ft 11 in) and a weight of around 80 kg (180 lb).


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