Red-tailed Catfish
Flat-nosed Catfish - Antenna Catfish
Family: Pimelodidae
Phractocephalus hemioliopterusThe Red-tailed Catfish is quite an attraction. The beautiful red tail and the white belly are unmistakable characteristics of this fish!
This fish gets very large. They are only able to be kept in a smaller aquarium as juveniles. Being fast growers they will quickly need a larger and larger aquarium. As they reach up to 3 feet or more (there are some reports of specimens reaching up to 5 feet!), they will ultimately need a very large tank. For the largest sized ones that could be 1500 gallons or more. This is a huge tank, making them not really suitable for most home aquarists.
They are not very active and would prefer a large cave or den to hang out in. They can't be kept with smaller fish as they will become lunch sooner or later. This fish has a big mouth and a hearty appetite. Even though the Red-tailed catfish is one of the larger fish in the Amazon, this is not a food fish for the natives. It has a dark colored flesh and the natives will only eat white flesh!
There is only one species in the genus Phractocephalus, the Red-tailed Catfish and a unique phenomena with this fish, as stated by author Hans A Baensch in Aquarium Atlas Volume 2, is that "...the red colored tail fin secrets a substance which colors the hands an intense red on contact".
For more Information on keeping this fish see:
Guide to a Happy, Healthy Freshwater Aquarium
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- Temperament: Large Aggressive - Predatory
- Aquarium Hardiness: Difficult to Impossible
- Aquarist Experience Level: Advanced
- Diet Type: Omnivore
- Minimum Tank Size: 2,000 gal (7,570 L)
- Temperature: 68.0 to 79.0° F (20.0 to 26.1° C)
- Range ph: 5.5-7.2
- Hardness Range: 3 - 12 dGH
- My Aquarium - Enter your aquarium to see if this fish is compatible!
- Beginner Fish - Freshwater fish for beginners
- Community Fish - Peaceful Freshwater fish
- Hardy Fish - Hardy Freshwater fish
- Similar size fish - Fish that are 1 inch bigger or smaller
- Coldwater Fish - Looking for cold water fish? (65 °)
Habitat: Distribution / Background
The Red-tailed Catfish are found in South America in the Amazon river, Rio Negro, Venezuela and Guyana. Prefers deep pools in rivers.
- Scientific Name: Phractocephalus hemioliopterus
- IUCN Red List: NE - Not Evaluated or not listed
The Red-tailed Catfish are dark grey on the top of the body covered with small darker spots. The shovel-like mouth is as wide as the body and the lower part of the mouth white. The white coloration under the mouth extends in in broad horizontal stripe to the tailfin. As a juvenile it joins with the white under the mouth, as it gets older, it is broken up by the dark grey coloration. The tip of the dorsal fin and the tail fin are slightly pinkish red. The eyes are set on either side of the head near the top.
- Size of fish - inches: 53.0 inches (134.62 cm) - There are reports of fish reaching sizes upwards of 5 feet in the wild, although the largest doccumented size was 53 inches.
- Aquarium Hardiness: Difficult to Impossible - This fish requries a massive tank and a diet of live fish. It is generally agreed upon that is is not really suited for the home aquarium at all.
- Aquarist Experience Level: Advanced - This fish is too large for all but the most extremely oversized of tanks.
Red-tailed Catfish are omnivorous but prefer meaty foods. As juveniles, they will generally eat all kinds of live, fresh, and flake foods. To keep a good balance give them a high quality flake food or pellet everyday. As they grow go you can go to higher percentages of either pellets or live foods.
- Diet Type: Omnivore
- Flake Food: No
- Tablet Pellet: Yes - This fish will ocassionally accept processed food but prefers a diet of live prey or meaty foods.
- Live foods (fishes, shrimps, worms): Some of Diet
- Vegetable Food: Some of Diet
- Meaty Food: Most of Diet
- Feeding Frequency: Weekly - Juveniles should be fed about every other day, but as the fish ages this should be reduced to a weekly feeding. Reduced activity levels and its preference for high protein diet will otherwise lead to excessive weight gain.
- Water Changes: Bi-weekly
- Minimum Tank Size: 2,000 gal (7,570 L) - Juvenille specimens will quickly outgrow a small tank, and if kept in overly cramped quarters this species will die very young. This fish is active and likey plenty of swimming space which is difficult to offer a fish of this size.
- Substrate Type: Any
- Lighting Needs: Moderate - normal lighting
- Temperature: 68.0 to 79.0° F (20.0 to 26.1° C)
- Range ph: 5.5-7.2
- Hardness Range: 3 - 12 dGH
- Brackish: No
- Water Movement: Moderate
- Water Region: Bottom - These fish will swim in the bottom of the aquarium. As they get older, they may stay motionless for long periods of time.
The Red-tailed Catfish are generally a good community fish with tank-mates their own size. Not much is known about keeping more than one in the same aquarium. Don't keep with fish that are much smaller since they are predaceous.
- Venomous: No
- Temperament: Large Aggressive - Predatory - Peaceful although somewhat territorial. Red-tailed Catfish are highly predatory.
- Compatible with:
- Same species - conspecifics: Yes
- Peaceful fish (): Threat
- Semi-Aggressive (): Threat
- Aggressive (): Threat
- Large Semi-Aggressive (): Safe
- Large Aggressive, Predatory (): Safe
- Shrimps, Crabs, Snails: Safe - not aggressive
- Plants: Safe
Not known.
The Red-tailed Catfish have not been successfully bred in aquariums.
- Ease of Breeding: Unknown - This fish is too large to be bred in a home aquarium.
The Red-tailed Catfish is available from time to time and is usually expensive.
Animal-World References
Freshwater Fish and Plants
Tropical Fish ~ Freshwater Fish ~ Aquatic Plants
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