Hyrtl's tandan
Neosilurus hyrtlii
Hyrtl's catfish features a robust, elongated body with a dark brown to olive-green coloration and distinct, long barbels on the snout.
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About the Hyrtl's tandan
A sleek Australian eel-tail catfish with the anal and caudal fins fused into an eel-like tail, it cruises the bottom at night and forms loose shoals. Calm toward similarly sized fish but an eager predator of bite-size tankmates, it grows big and appreciates long, open swimming space.
Also known as
Quick Facts
Size
34 cm SL
Temperament
Semi-aggressive
Difficulty
Intermediate
Min Tank Size
92 gallons
Lifespan
up to 5 years
Origin
Australia
Diet
Carnivore - sinking pellets, prawns/shrimp, mussels, insects; will eat small fish
Water Parameters
22-28°C
6.8-8
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Calculate heater sizeCare Notes
- Give Hyrtl's tandan a big, long tank - 92 US gallons minimum - because it grows to about 34 cm SL and likes open bottom cruising.
- Keep freshwater at 22-28 C and pH 6.8-8.
- Layout: leave long open stretches of floor with some sturdy cover; it cruises the bottom at night and appreciates space to roam.
- Feed a carnivore diet of sinking pellets plus meaty items like prawns/shrimp, mussels, and insects; offering food after lights-out suits its nocturnal habits.
- Choose tankmates its own size or larger and robust; it is semi-aggressive and will eat any fish small enough to swallow.
- It can form loose shoals, but only attempt more than one in a very large tank to keep the peace and provide room.
- Plan stocking around an up-to-5-year lifespan and its adult size, not juvenile looks.
Compatibility
Good Tankmates
- A small group of Hyrtl's tandans of similar size in a very large tank (6 ft+), with multiple caves and sightline breaks; they form loose shoals and spread any dominance
- Large rainbowfish (Melanotaenia/Chilatherina/Glossolepis) 12-15+ cm, kept in groups; fast midwater swimmers, too big to swallow, match 22-28 C and neutral-alkaline water
- Big, armored plecos 20+ cm (e.g., sailfin/common types); tough, mostly ignored, and occupy different feeding niches
- Bala sharks in a proper shoal and only in very large tanks; large, fast, upper-level fish that are not easily preyed on
- Robust, even-tempered cichlids 20+ cm that tolerate neutral to slightly alkaline water and 24-28 C (avoid hyper-aggressive strains)
Avoid
- Anything small enough to fit in its mouth (e.g., tetras, danios, guppies, small rainbowfish); will be hunted, especially at night
- Shrimp, small crayfish, and other crustaceans or snails; treated as food
- Nippy or harassing fish (tiger barbs, serpae-type barbs, aggressive 'shark' minnows) that strike fins or stress bottom cruisers
- Very aggressive or highly territorial bruisers (jaguar/flowerhorn/red devil cichlids, similar large predators) that can injure or outcompete it
Hyrtl's tandan (Neosilurus hyrtlii) is a sleek Australian eel-tail catfish. The anal and caudal fins fuse into an eel-like tail, and adults reach about 34 cm SL. Mostly active from dusk onward, it cruises the bottom in loose groups and stays calm with similarly sized fish, but it is an eager predator of anything it can swallow. Lifespan is up to 5 years.
Predatory by nature - it will eat small fish.
Origin and habitat
Native to Australia, this freshwater catfish spends its time near the bottom and is most active at night. In nature it is often seen in loose shoals rather than tight schools, a pattern you may also notice in large aquaria with more than one individual.
Aquarium setup and water conditions
This is a large, cruising catfish that appreciates length over height. A minimum of 92 US gallons is specified, and a long tank with open floor space lets it patrol without constantly turning. Use smooth sand or rounded gravel to protect the barbels, and provide some broad shelters (driftwood, sturdy caves, large pipes) so it can rest out of bright light during the day. Keep lighting on the dimmer side or add floating cover if the fish seems skittish.
- Temperature: 22-28 C
- pH: 6.8-8
- Freshwater; stable, well-filtered, well-oxygenated water
Arrange decor so there is a clear runway along the front or back glass. This species values long, unobstructed routes more than intricate rock piles.
Diet and feeding
A strict carnivore. Offer quality sinking carnivore pellets as a staple, with regular portions of prawns/shrimp, mussels, and suitable insects. Feed primarily after lights out to match its crepuscular/nocturnal habits, dropping food where it will reach the bottom quickly. It will consume small fish, so do not use feeder fish and keep bite-size tankmates out of the setup.
Behaviour and tankmates
Temperament is best described as semi-aggressive. It is generally calm toward fish it cannot eat, but it is assertive at feeding time and anything small enough will be treated as prey. Individuals may tolerate conspecifics in spacious tanks, reflecting their loose-shoaling nature, but crowding can lead to jostling.
- Choose robust, similarly sized tankmates that are too deep-bodied or large to swallow.
- Avoid small community fish.
- Provide multiple feeding spots so midwater fish do not outcompete this bottom cruiser.
Common issues to watch for
- Predation on small tankmates - stock with fish that are not bite-size.
- Barbel wear or mouth abrasions - use smooth substrates and maintain excellent water quality.
- Underfeeding due to daytime hiding - target-feed sinking foods after lights out.
- Waste load from meaty foods - size filtration and maintenance for a large, carnivorous fish.
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