Sailfin Marbled Pim Catfish (Leiarius pictus)

Choose a Sailfin Pim Catfish for a very large, mature aquarium

The Sailfin Pim Catfish, sold here as the Sailfin Marbled Pim Catfish, is Leiarius pictus, a long-whiskered catfish of the family Pimelodidae from South America. Seriously Fish and Planet Catfish also list the names painted catfish, saddle catfish and marbled sailfin catfish, and older literature calls it Bagrus pictus or Sciades pictus. Its species name means "painted", after the spots of the adult, and its common name comes from the tall, sail-like dorsal fin that sets it apart from its relatives.

Seriously Fish places it in the Orinoco basin of Colombia and Venezuela and parts of the Amazon drainage in Peru and Brazil, and FishBase adds the Essequibo basin. It lives in large rivers and lakes, lurking among submerged tree roots and other refuges by day and coming out at night to feed. This is a true "tankbuster": a fish of about 60 cm that can live for more than 20 years, for keepers who already run, or are building, a very large system. FishBase lists it as Least Concern on the IUCN Red List (assessed in 2020).

Tell it apart from look-alike catfish

Planet Catfish describes the adult as dark brown with darker spots and a lighter underside. Young fish show two pale bands: the first runs from the base of the dorsal spine towards the pelvic fin and then along the body to the tail, and a thinner one runs parallel to it from the middle of the dorsal fin. Large round spots mark the dorsal, adipose and tail fins, and the barbels are ringed light and dark. The colour fades a little and the tail lobes become more pointed with age.

Select one fish and plan for twenty years

One purchase supplies one live Sailfin Marbled Pim Catfish in the standard size we receive: a juvenile far smaller than the adult. Sex is not specified, and Seriously Fish says this species is virtually impossible to sex by its outward appearance, although adult females are probably stockier than males. The gallery images are representative, prepared from a reference photograph, and do not show the individual you will receive.

Decide whether you can give it a lifetime home

• Space: the system must hold a 60 cm adult, not just today's juvenile.
• Time: Seriously Fish says it can live for more than 20 years.
• Company: it is territorial towards its own kind, so plan for one.
• Running costs: heating, filtering and changing water in a system of this size is a serious ongoing commitment.

Read our delivery and Live Arrival Guarantee policy before ordering a large fish.

Plan the aquarium around a 60 cm adult

Seriously Fish and Planet Catfish give a maximum of 600 mm standard length, measured without the tail, and FishBase gives 60 cm total length. Seriously Fish asks for an aquarium base of at least 240 × 90 cm, and for a fully grown fish an aquarium of 240 × 90 × 120 cm, about 2,592 litres. Growth can be fast: Chris Ralph, writing for Planet Catfish, rescued a fish of about 16 in that grew to about 28 in over almost four years in his 12 × 3 × 4 ft indoor tropical pond.

The same article reports that this catfish can become stressed when its long maxillary barbels touch the front and back of a too-narrow aquarium at the same time, and may then try to leave the tank, so depth from front to back matters as much as length, and a tight-fitting cover is essential. Our tank volume calculator converts your measurements into litres.

Run a four-step space check

1. Measure the base: at least 240 cm long and 90 cm from front to back.
2. Check the height: 120 cm for a fully grown fish, per Seriously Fish.
3. Size the filtration: OATA notes that several large filters, or a pond filter, may be needed for fish of this size.
4. Fit a strong, tight lid: recommended by Planet Catfish for this species, and by OATA for large, jumpy fish.

Build a night-cruising space with a daytime refuge

Planet Catfish recommends a large, spacious tank with open space for night-time cruising and a large, shady bogwood root or pipe for it to retreat to by day. It also advises placing the heater in the open, not in the spot where the catfish might try to hide. OATA adds that large fish can knock over décor, so rocks must be secured and heaters protected, and that the substrate must have no sharp edges and be easy to keep clean.

Divide the footprint by function

Set water values within the published range

Here the sources agree closely, which makes the target simple.

That is a broad range, but check your tap water against it before you buy, particularly in very hard-water areas; your water company publishes figures for your postcode, and our water matcher compares them with this fish. Our water chemistry guide explains each reading. Stability matters more than any single number in a system this size.

Separate habitat values from waste readings

OATA gives these limits for every very large fish and notes that even small amounts of ammonia and nitrite can stress them.

Filter for big meals and big waste

A large predator eats large meals and produces a lot of solid waste in a short time. Choose filtration that can handle the whole system's volume several times over, with strong mechanical stages to catch solids and generous biological media, and keep spare capacity for the day after a meal. Our guide to aquarium filtration explains how to build that combination.

Follow a weekly maintenance sequence

1. Test ammonia, nitrite, nitrate, pH and hardness every week, as OATA advises.
2. Change at least 25% of the water each week, OATA's minimum.
3. Treat new water with a conditioner that removes chlorine and chloramine, and match its temperature.
4. Remove uneaten food and solid waste promptly after each meal.
5. Rinse filter media only in removed tank water, never under the tap.

Feed large, meaty meals, sparingly

Seriously Fish describes it as piscivorous by nature but quick to accept dead foods in captivity, and lists prawns, mussels, cockle, lancefish and earthworms as favourites. Planet Catfish adds floating sticks or pellets and catfish pellets. Seriously Fish advises against beef heart, chicken and live feeder fish.

Build one measured meal

• Set the rhythm: Seriously Fish advises feeding juveniles every other day and adults a single meal a week at most. This species-specific guidance is sparser than OATA's general once-a-day rule for large fish.
• Size the food: whole prawns, mussels or lancefish matched to its mouth.
• Feed in the evening: it is a night-time feeder.
• Remove leftovers: take out uneaten food the same night or next morning.
• Watch the body: a steadily growing fish with a gently rounded belly is right; a bloated one is overfed.

Introduce it to a mature system

Large fish may travel in boxes or buckets as well as bags. Use OATA's floating method: lights off, float the sealed bag for about 10 minutes to equalise the temperature, add small amounts of aquarium water over up to 20 minutes, then guide the fish out with as little transport water as possible. OATA warns that most catfish carry spines on their front fins, so move it in a container rather than a net where you can. Our guide to acclimatising new fish covers each step.

Use a first-week checkpoint plan

Read its behaviour and act on changes

Expect a Sailfin Pim Catfish to hide by day and cruise the open floor at night, feeling its way with barbels that can move independently. Seriously Fish describes it as actually quite peaceful with fish of its own size. Chris Ralph's feature describes a real character that learned to take food from his hand, and that once picked up a large Oscar that was in its way at feeding time, carried it round the pond a couple of times and left it, disorientated, in a corner.

Pair each observation with an action

Screen tank mates by size and family

Seriously Fish says it will not hesitate to eat any smaller fish, and that it is territorial towards its own kind and towards other large pimelodid catfish. It suggests large doradids such as Oxydoras niger, Megalodoras uranoscopus and Pterodoras granulosus as companions, and in a very deep aquarium larger characins, cyprinids, the South American arowana and Cichla species. Planet Catfish adds Oscars and larger characins.

Decide from the suits and avoid list

From our range, suitable companions for a big system include the Oscar Cichlid (see our Oscar care guide), the Silver Arowana and the Monoculus Peacock Bass, each introduced at a size the catfish cannot swallow. Do not mix it with our Red-Tailed Catfish or Tiger Shovelnose Catfish, which are large pimelodids. If you want the spotted pim look in a community-sized fish, the Pictus Catfish (Pimelodus pictus) and our other Pimelodus catfish stay far smaller. Browse all South American catfish, our centrepiece fish, rare and collector fish and catfish and plecos, and check every mix with our tank mates tool.

Know the limits of breeding

Seriously Fish describes breeding as unreported in the hobby, and Planet Catfish records no known aquarium spawnings, most likely because of the size of fish and aquarium involved. Treat this as a single, long-lived display fish rather than a breeding project.

Answer Sailfin Pim Catfish buying questions

What is a Sailfin Marbled Pim?

It is Leiarius pictus, a large long-whiskered catfish of the family Pimelodidae from the Amazon, Orinoco and Essequibo basins of South America. It is also sold as the Sailfin Pim, Painted Catfish and Saddle Catfish.

How big does Leiarius pictus get?

Seriously Fish and Planet Catfish give 60 cm standard length, measured without the tail, and FishBase gives 60 cm total length. One UK keeper writing for Planet Catfish recorded his fish growing from about 16 in to about 28 in over almost four years.

What size aquarium does it need?

Seriously Fish gives a minimum base of 240 × 90 cm, and for a fully grown fish an aquarium of 240 × 90 × 120 cm, about 2,592 litres. An indoor heated pond is a sensible alternative.

Is it the same fish as the Pictus Catfish?

No. The Pictus Catfish sold for community tanks is Pimelodus pictus, which Seriously Fish gives as 120 mm standard length. Leiarius pictus shares only the species name and grows about five times longer.

How often should I feed an adult?

Seriously Fish advises feeding juveniles every other day and adults a single meal a week at most. Use prawn, mussel, cockle, lancefish, earthworms and large catfish pellets.

Will it eat my other fish?

Yes, if they are small enough. It is a fish-eater by nature and will swallow any tank mate that fits in its mouth, so keep it only with fish of similar size.

Can I keep two together?

Seriously Fish says it is territorial towards its own kind and other large pimelodid catfish. Unless the system is exceptionally large, keep one.

How long does it live?

Seriously Fish says it can live for more than 20 years, so buying one is a long commitment.

Consult the care references

• Seriously Fish: Leiarius pictus (Sailfin Pim): names, distribution, habitat, size, aquarium base and volume, water values, feeding frequency, tank mates, sexing and lifespan.
• FishBase: Leiarius pictus: classification, maximum length, water range, distribution and IUCN status.
• Planet Catfish: Leiarius pictus: names, synonyms, etymology, identification, sexing, water values, feeding, décor and tank mates.
• Planet Catfish Catfish of the Month, April 2003: Leiarius pictus: a UK keeper's growth record, juvenile and adult appearance, barbels, behaviour and lid advice.
• Seriously Fish: Pimelodus pictus (the smaller pictus catfish): size and aquarium base of the much smaller pictus catfish, to avoid a mix-up of names.
• OATA: How to look after very large fish / tankbusters: UK guidance for very large fish on aquarium size, filtration, décor, cover and feeding.
• OATA: How to look after freshwater catfish: UK guidance for catfish on water quality, sand, introduction, handling, feeding and health signs.
• Tropical Fish Co delivery policy: current dispatch days and Live Arrival Guarantee terms.