Redtail Catfish: Size, Food, Tank Mates, Care…

The Redtail Catfish is a giant catfish from the freshwaters of South America.

These beautiful fish have a lively personality and will make an impression in any tank.

However, they can reach amazing lengths and will eat anything that fits in their mouth.

Because of this only experienced aquarists with access to extremely large tanks should think about keeping this flashy-tailed fish.

Do you have the right tank and experience to keep the Redtail Catfish?

Keep reading to find out…

Redtail Catfish Overview

Redtail Catfish

The Redtail Catfish (Phractocephalus hemioliopterus) is a giant freshwater fish found in South American river basins including the Amazon, and Orinoco.

These large fish have gained popularity because of their bright eye-catching colors and their sheer size.

A mature Redtail can measure between 3-4 feet!

These mighty fish are part of the Pimelodidae family (the same as Pictus Catfish) and they can live for up to 15 years in captivity. In their homeland they have gained great respect from the locals because of their aggressive tendencies.

Do not be fooled by their small size as juveniles. They will grow roughly 1 inch per week and need at least a 1,500 gallon tank.

Juvenile Redtail Catfish will cost between $20-40 whilst mature Redtails will set you back around $200.

Key Facts:

  • Experience Required: Advanced.
  • Nicknames: Banana Catfish.
  • Color Forms: Gray and white with red tail.
  • Size: 3-4 feet.
  • Tank Size: Minimum 1500+ gallon.
  • Tank Temperature: 68°F-80°F.

Redtail Catfish Close Up


  • Active temperament
  • Fun and bold colors
  • Easy to feed
  • Long lifespan

  • Advanced level care
  • Need a huge tank
  • Rapid growth rate
  • Can be aggressive


Redtail Catfish have the classic catfish shape with thick bodies that taper progressively thinner towards the tail.

They have long barbels and, like other catfish, they have a flat underside which is most notable under their head.

As juveniles they measure around 2 inches.

However, their rapid growth is astounding with mature Redtails reaching up to 4 feet in length and weighing 80 pounds.

Their big bodies are typically dark gray with speckled patterns on their heads and upper body.

Below their heads they have a white belly. This white color can also extend from the pectoral fins to the base of the caudal fins. You will notice a yellowish white stripe continues down to their Redtails; this is where their nickname Banana Catfish comes from.

Finally, their caudal fins and the tips of their dorsal fins are red.

Telling male and female Redtail Catfish apart is very difficult and they are often indistinguishable.

Habitat and Tank Conditions

Redtail Catfish Substrate

Redtail Catfish are bottom dwellers and spend the majority of their time near the freshwater benthos.

Given their size they need at least a 1500 gallon tank.

You should provide them with the following water conditions:

Tank Parameter Requirement
Minimum Tank Size 1500-2000 Gallons
Tank Type Freshwater
Temperature 68-80°F
pH 6.0-7.5
Hardness 3-12 dGH
Flow Light
Substrate None

Maintaining steady and comfortable water conditions for such large tanks can be challenging. Only Advanced aquarists should take on this challenge.

They will thrive best in warm and moderately soft water.

Naturally they are accustomed to low light so dim lighting is preferable. Too much light can actually cause stress so make sure you provide lots of shaded areas and caves where they can retreat if they become stressed.

Because this fish is so boisterous you should use external heaters and filters.

You do not need powerful filters because Redtail Catfish are slow swimmers and used to slow-flowing waters.

For the substrate, no substrate is the best option as they will try to feed on any substrate they can get in their mouths.

Sandy benthos is the most suitable if you must have substrate.

Again, only a few décor or plants should be added to this tank set up. They won’t last long as your Redtail will eat them!

That being said, providing shaded areas can be beneficial. Make sure any décor or plants are too big to fit in your Redtail’s mouth.

Redtail Catfish are minimalists!

All this means that your tank won’t be the prettiest, but your tank inhabitants will be happy and healthy.

What Size Aquarium Do They Need?

Your Redtail Catfish will need at least a 1500 gallon tank.

Redtail Catfish Tank Mates

These Catfish are natural born predators that will eat anything they can fit into their mouth.

It is common for Redtail Catfish to be kept alone in aquariums.

However, despite their semi-aggressive nature, they can be peaceful when kept with the right tank mates under comfortable conditions that simulate their natural environment.

Almost all freshwater fish that are similar in size, or larger, can make good tank mates.

Non-aggressive fish will work best and reduce the aggression within your home setup. You just need to make sure these fish can survive in the same water conditions. Some good tank mates are:

There is always a possibility that your Redtail might attempt to snack on tank mates even if you think they are too big to be eaten, so be wise in which tank mates you choose!

Keeping Redtail Catfish Together

Redtail Catfish should not be kept together.

When kept together their aggressive and territorial tendencies come out. It is far better to keep them with other similar sized or larger fish species to avoid these territorial behaviors.

Redtail Catfish Swimming

Care Guide

Caring for a Redtail Catfish is a big task.

These fish can reach 3-4 feet long and weigh up to 80 pounds.As with any larger freshwater fish, this creates greater challenges in their care needs.

Bigger fish means bigger tanks and therefore bigger needs.

One of the key parts of their care is maintaining a large tank.

They need weekly 30% water changes. Additionally, given their messy feeding habits, tanks can get murky and messy so they should be cleaned after each feeding session. Because they eat so much they create a lot of waste. Increased waste in tank setups will alter the water chemistry and quality so you need to make sure your pump can handle the waste.

Despite being generally hardy fish, Redtail Catfish can still be affected by diseases and illnesses.

Keeping the tank conditions optimal will reduce the likelihood of illnesses including, fin rot, and skin or gill flukes.

Fin rot is a common bacterial or fungal infection that causes the decay of the fins and skin. A clear sign of fin rot can be the tattered and dull appearance of the fins.

Monitoring activity levels will also provide a good indication of fin rot, as the fish become slow and sluggish and have a loss of appetite. It can be treated with medication, but be careful as some Redtails can be sensitive to medication.

Gill and skin flukes are small parasites that can inhabit a fish’s skin or gills. They can be very harmful and cause secondary infections in your fish.

Good indicators of these parasites include loss of appetite and breathing difficulties.

Again, they can be treated with medication, but making sure your fish have enough tank space will help reduce the chance of infection.

Another easy way to prevent contamination is to quarantine new décor and fish before adding them to the tank.


Redtail Catfish are omnivores and typically eat anything they can find.

These predators need protein rich diets and often feed on small fish, crustaceans, and insects. As bottom dwelling fish they scour the benthos for prey.

In an aquarium you can feed them sinking pellets.

Using sinking pellets will mean that they reach the bottom of the tank where your Redtails will be waiting.

Other ways to imitate natural feeding behaviors include using both live and frozen forms of the organisms they usually prey on.

You can try feeding them:

  • Small fish
  • Crayfish
  • Worms
  • Shrimp

Adults should be fed weekly; however, this depends on the activity level of your Catfish. If you have a particularly active Redtail then increase how often you feed them.

We recommend starting by feeding them twice weekly, making sure to monitor them to see if this is right for your Redtail.

One way to determine how often you feed your Redtail Catfish is simply by observation.

After feeding they become slow and sluggish.

If you see them become increasingly active again, you know you can feed them again soon. Be careful not to overfeed your Catfish as they are prone to overeating.


Redtails are catfish and this means you can expect their behavior to be similar to other catfish.

They will spend most of their time exploring the bottom depths of the tank. They will do this no matter who or what you add to their tank.

Giving these big fish enough space to roam is a top priority.

Without enough space they will become more aggressive. Aggressive tendencies can occur towards other large fish, especially when other Redtail Catfish are involved. However, most of their aggressive behaviors relate to feeding and predatory instincts.

Redtails have even been known to show aggression towards humans! Usually this is from fingers or hands in their tanks being mistaken for food.

As a predatory fish there will always be an instinct to eat other fish and pretty much anything else it can find.


Redtail Catfish are oviparous.

This means they lay eggs that will hatch later.

However, it is unlikely you will be able to see this in your home tank given the difficulties in sexing them. This makes them very difficult to breed in captivity, if not impossible.

If determining their sex was not enough of a challenge keeping two Redtail Catfishs together can cause territorial and aggressive behaviors that further complicate breeding.

Typically, females will lay up to 20,000 eggs at one time.

The male will later spread sperm over the eggs to fertilize them.

Fertilized eggs will then hatch approximately 10 days later.

In the wild the male will protect the juveniles for about 1 week after hatching. After a week they are left to navigate the wild themselves.

Most Redtails are bred in farms or fisheries for commercial trade. Often these farms are in lakes or very large ponds. It is not recommended that you attempt to breed them yourself.

Species Summary Table

Redtail Catfish
Other Common Names: Banana Catfish
Scientific Name: Phractocephalus hemioliopterus
Family Name: Pimelodidae
Distribution: South American river basins
Size: 3-4 feet
Color: Gray with red tail
Care Level: Advanced
Temperament: Semi-aggressive
Lifespan: 15 years
Minimum Tank Size: 1500 gallons
Tank Mate Compatibility: Peaceful larger fish


This large Catfish is only suitable for experienced aquarists with huge tanks.

Despite their small size as juveniles, they will quickly grow and need a 1500 gallon tank.

Once you have the right tank set up, be prepared to care for this fish for a long time as they can live for up to 15 years.

Although Redtail Catfish may seem like big friendly giants, they will eat anything they come across.

So be careful what you put in their tanks!

What is the biggest Redtail Catfish you have ever seen? Let us know in the comments section below…