Black Driftwood Catfish (Trachycorystes trachycorystes)

Choose a black driftwood catfish only for a species set-up

The Black Driftwood Catfish (Trachycorystes trachycorystes) is a large, nocturnal predator from northern South America. Planet Catfish describes it as slender and the same colour all over, usually black, belly included, with a protruding lower jaw that makes the species easy to recognise. It spends the day wedged into wood and comes out after dark to hunt.

It belongs to the driftwood catfish family, Auchenipteridae, subfamily Auchenipterinae. FishBase records it from the Amazon basin, the Essequibo basin in Guyana and the Orinoco basin in Venezuela. The genus name combines Greek words for rough and helmeted, after the rugged bony shield on the head. Planet Catfish notes that it is the Trachycorystes species most often exported, though only now and then.

Check the names on the label

Some keepers report brown rather than black fish. Planet Catfish and ScotCat both suggest a brown form may turn out to be a separate species.

Decide from the complete care picture

Know exactly what you receive

One purchase supplies one live Black Driftwood Catfish. The size option is "Standard": the fish is sent at the size currently available, which will be far smaller than the adult. Sex is not chosen or guaranteed.

The photographs show the type of fish, not the individual you will receive. Colour can range from black to dark brown, as noted above.

Plan for the adult, not the juvenile

• Adult size: 35 cm standard length, according to FishBase, Planet Catfish and ScotCat.
• Sexes: Planet Catfish says males have a genital papilla, stay smaller than females and may develop thickened barbels or larger dorsal spines. ScotCat adds that adult males have a thickened anal fin, while the female's genital opening is enlarged.
• Numbers: buy one. Planet Catfish warns that it will attack its own kind.

Read our delivery and Live Arrival Guarantee terms and have the aquarium set up and matured before you order.

Plan a very large aquarium

No source we checked gives a minimum aquarium size for this species, so plan from the adult size and from UK guidance on big fish. OATA's care sheet for very large fish, which includes large catfish, says an exceptionally large aquarium is needed, often over 500 litres. It also notes that sedentary species may not need the same volume as active swimmers. This catfish rests by day, but Planet Catfish stresses that it needs swimming space for its night-time activity as well as large hiding places.

Run a three-step space check

1. Fit the adult: the tank must comfortably hold a 35 cm fish turning around a large cave, not just the juvenile that arrives.
2. Count the volume: use our tank volume calculator and compare the result with OATA's guidance for very large fish.
3. Check the whole stock: any companion must also be large, and our stocking calculator helps you check the total load.

Fit a heavy, secure lid. Planet Catfish warns that this species may jump when first introduced, and OATA notes that large fish are often jumpy in a new home.

Build a dark refuge of wood

Planet Catfish recommends large pieces of driftwood as hiding places, which suits a fish named for living among sunken wood. Give it a cave or root tangle it can wedge into completely, with open sand in front for night patrols. Dim lighting, or a lighting period that ends in the early evening, lets you see it more often.

Divide the aquarium by function

OATA advises securing every rock and ornament and protecting heaters, because large fish disturb décor and can dislodge it. Its catfish care sheet also recommends sand or fine gravel to protect sensitive barbels.

Keep the water in the published range

Planet Catfish lists 23–29°C and pH 6.4–7.0 and describes the species as generally undemanding. ScotCat gives 23–27°C and pH 6.5–7.0. We suggest the overlap of the two: 23–27°C and pH 6.5–7.0. Neither source gives a hardness figure; OATA's general catfish range of 4–18 dGH is a reasonable guide.

Separate habitat values from waste readings

The pH band is narrow, so check where your tap water sits before you buy. Aim for a stable value close to the range rather than repeated chemical corrections. Use a conditioner at every water change to remove chlorine or chloramine. Our water chemistry guide explains pH, hardness and buffering.

Filter for a big predator's waste

A 35 cm meat-eater produces a lot of waste. OATA notes that very large fish may need several large aquarium filters, or even a pond filter, to control water quality and remove solid waste. Choose filtration for the adult fish from the start rather than upgrading after problems appear. Our filtration guide explains flow and media choices.

Follow a weekly routine

1. Test ammonia, nitrite and nitrate at least once a week, as OATA advises.
2. Change up to 25% of the water each week, and more if nitrate climbs.
3. Siphon uneaten food and waste from the sand, especially around the cave.
4. Check filter flow and clean prefilters, rinsing media in tank water only.
5. Check that heaters, rocks and wood are still secure.

Feed large, measured meals after dark

Planet Catfish says it eats everything that fits its very large mouth and prefers live food, but it also takes larger frozen foods and happily eats prepared foods; tiny foods such as daphnia are not suitable. ScotCat lists worm foods, frozen shrimp, bloodworm, chunks of frozen fish, tablets and pellets. With that range of frozen and prepared foods accepted, there is no need to offer live feeder fish.

Build one measured meal

• Staple: large sinking carnivore pellets or tablets.
• Frozen variety: thawed shrimp, chunks of frozen fish and large worm foods.
• Timing: feed shortly after the lights go out, close to its cave.
• Portion: an amount it clears that night; remove leftovers the next morning.

Overfeeding a large predator quickly fouls the water. If food is regularly left, reduce the portion. A fish that stops feeding is a reason to test the water, not to offer richer food.

Introduce it carefully

Add it only to a mature aquarium with zero ammonia and nitrite and the cave already in place. OATA notes that catfish are double-bagged because their spines can pierce a bag, and that most catfish carry spines on the pectoral fins and behind the gills, so take care when handling it. Our acclimatisation guide covers the floating method: lights off, about 10 minutes floating, then small amounts of tank water over up to 20 minutes before release.

Use a first-week checkpoint plan

Keep it alone or with very large, robust fish

This is the most important point on this page. Planet Catfish calls it an aggressive fish that needs a species tank with plenty of refuges, warns that it will attack its own kind, and says smaller fish will eventually be killed even if they can defend themselves well. ScotCat calls it one of the most aggressive catfish in the hobby, says it will quickly kill smaller tank mates as it grows, and concludes that it is basically a fish to keep on its own, though large cichlids may be possible.

Screen any companion against these rules

Driftwood catfishes are close relatives of the thorny or talking catfishes, such as our Striped Raphael Catfish, but that fish is exactly the kind of cave-user this predator would fight. Our Perugia's Woodcat belongs to the same family yet is a small fish that would be eaten, so never mix the two. If you are weighing up big South American catfish, compare the commitment with the Yellowtail Redtail Catfish, and browse our rare and collector fish, our catfish and plecos or the full South American catfish range.

Watch for problems early

Pair each sign with an action

OATA lists clear eyes, intact fins, no ulcers or bumps, normal swimming and steady breathing as signs of a healthy fish. Because this catfish is nocturnal, check it with a dim torch after dark as well as in daylight.

Compare it with a smaller driftwood catfish

Buyers often weigh this fish against the more widely kept common woodcat, Trachelyopterus galeatus, which also hides in wood by day. The two look and live alike, but they need very different set-ups.

Check the differences before you choose

The common woodcat figures come from Planet Catfish, FishBase and the ScotCat factsheet for that species. If you want a woodcat that can live with other large, peaceful fish, the smaller species is the easier choice. Choose the Black Driftwood Catfish only if you can give it a tank of its own.

Breeding notes

Planet Catfish lists breeding as unreported in the aquarium. FishBase records internal fertilisation, as in other driftwood catfishes: the male's modified anal fin, which ScotCat describes, transfers sperm to the female. Breeding is not a realistic aim for most keepers, and aggression between adults makes keeping a pair risky.

Answer Black Driftwood Catfish buying questions

What is a Black Driftwood Catfish?

It is Trachycorystes trachycorystes, a large, usually all-black catfish of the driftwood catfish family Auchenipteridae from the Amazon, Essequibo and Orinoco basins. It is also sold as the Black Woodcat or Iron Head Driftwood Catfish.

How big does it get?

FishBase, Planet Catfish and ScotCat all give 35 cm standard length. Males stay smaller than females, but plan for a 35 cm fish.

Is the Black Driftwood Catfish peaceful?

No. Planet Catfish describes it as aggressive and recommends a species tank, and ScotCat calls it one of the most aggressive catfish in the hobby. It kills smaller fish and may attack its own kind.

What size aquarium does it need?

No source gives a species minimum. OATA says very large fish usually need an exceptionally large aquarium, often over 500 litres, though sedentary fish can need less than active swimmers. Plan the tank around a 35 cm adult, with a cave and room to move at night.

What does it eat?

It is a predator with a very large mouth. ScotCat lists worm foods, frozen shrimp and bloodworm, chunks of frozen fish, tablets and pellets, and Planet Catfish says it takes prepared foods readily. Live feeder fish are not needed.

What water does it need?

Keep it at 23–27°C and pH 6.5–7.0, where the Planet Catfish and ScotCat ranges overlap, with zero ammonia and nitrite. Planet Catfish describes it as generally undemanding about water.

Can it be kept with other fish?

Only with very large, robust fish, and a species tank is the safer plan. Avoid smaller fish, slow fish such as adult angelfish, and fish that would compete for its hiding places.

How many fish come with one purchase?

One live fish of the standard size currently available.

Consult the care references

• FishBase: Trachycorystes trachycorystes — classification, distribution, maximum length and reproduction.
• Planet Catfish: Trachycorystes trachycorystes — names, identification, sexing, water values, feeding, décor and compatibility.
• ScotCat: Trachycorystes trachycorystes — aggression, size, water values, sexing and diet.
• OATA: How to look after freshwater catfish — UK group-level catfish guidance on water quality, substrate, introduction and handling.
• OATA: How to look after very large fish (tankbusters) — UK guidance on very large fish: aquarium size, filtration, cover and décor.
• OATA: How to test water quality in your freshwater aquarium — UK guidance on water testing, conditioners and weekly water changes.
• Planet Catfish: Trachelyopterus galeatus — names, size, water values, feeding, décor, compatibility and sexing of the common woodcat.
• ScotCat factsheet: Trachelyopterus galeatus — UK history, tank length, décor, colour, compatibility and diet of the common woodcat.
• Tropical Fish Co delivery policy — current dispatch days and Live Arrival Guarantee terms.