Spotted Shovelnose Catfish (Hemisorubim platyrhynchos)

What is a Spotted Shovelnose Catfish?

The spotted shovelnose catfish (Hemisorubim platyrhynchos) is a large, predatory member of the Pimelodidae family — the long-whiskered catfishes of South America. Its most distinctive feature is an extremely flattened, spatula-shaped snout, used to root along riverbeds and ambush prey that ventures too close. The body is silver-white on the flanks with a pale belly, marked by a scattering of bold dark-brown or black spots that give the fish both its common name and a genuinely dramatic appearance. Long, trailing barbels extend from the upper jaw, adding to the prehistoric look.

Adults grow to around 55 cm (22 in) in the aquarium, making this one of the more manageable large shovelnose catfishes available to hobbyists. It is considerably smaller than the closely related redtail or tiger catfish, which can exceed 100 cm (40 in), and is sometimes promoted as a practical alternative for keepers who want that shovelnose silhouette without needing a truly exhibit-scale system. “Manageable” is relative, however: at half a metre and with a substantial bioload, this is still firmly a specialist fish requiring dedicated infrastructure and at least 10–15 years of commitment.

Where does the Spotted Shovelnose Catfish come from?

Hemisorubim platyrhynchos is native to the Amazon and Orinoco river basins across tropical South America, with records from Brazil, Peru, Colombia, Venezuela and neighbouring countries. It inhabits the deeper, slower sections of large rivers and associated flooded lowlands, where it lies low on sandy or muddy substrates during the day, becoming more active at dusk and through the night.

Wild fish experience seasonal variation in water conditions — the Amazonian wet season brings cooler temperatures, lower pH and soft, tannin-stained water; the dry season sees warmer, somewhat harder conditions. The species is adapted to this range, which is reflected in its broad captive-care parameters. Imported specimens enter the trade mainly as juveniles; wild-caught adults are occasionally seen but are harder to acclimatise.

What tank setup does a Spotted Shovelnose Catfish need?

The minimum tank size for a single adult is 570 litres (150 US gal). This is a non-negotiable floor, not a comfortable target — a well-grown fish at 50–55 cm (20–22 in) needs the full length of a 150-plus-gallon tank to turn comfortably. A wide, low footprint is far more appropriate than a tall display tank: floor space matters more than water column height for a species that lives exclusively at the bottom.

Substrate should be fine sand or smooth rounded gravel — the shovelnose frequently rests directly on the bottom and rests on or roots along the substrate, and sharp gravel can abrade the sensitive barbels and underbelly over time. Furnish with large smooth rocks, sections of thick driftwood and PVC or ceramic pipe hides to provide shaded daytime refuges. Lighting should be moderate to dim; this species is naturally crepuscular and will be stressed and inactive under harsh, unbroken light.

Filtration must be substantial. A fish of this size produces a significant ammonia and waste load, so over-spec the filter by at least 50 % of the tank volume per hour turnover and add mechanical pre-filtration to keep solids from fouling the biological media. A sump setup is ideal. Gentle-to-moderate flow is fine; high turbulent flow is unnecessary. Keep the tank well covered — large catfishes are capable of unexpected bursts of speed and can clear a low-sided tank.

What water parameters does the Spotted Shovelnose Catfish need?

• Temperature: 22–28 °C (72–82 °F). Aim for the middle of this range — 24–26 °C (75–79 °F) — as a stable year-round target.
• pH: 6.0–7.5. Slightly acidic to neutral water mirrors the Amazonian origin; avoid alkaline conditions.
• Hardness: 2–12 dGH. Soft to moderately hard; very hard tap water should be blended with RO.
• Ammonia / Nitrite: 0 ppm at all times; a fish of this size will reach toxic levels quickly in a cycling or inadequately filtered system.
• Nitrate: Keep below 20–30 ppm with regular large water changes (25–30 % weekly or fortnightly at minimum).

Stable parameters matter more than hitting exact numbers. Temperature swings and sudden pH shifts stress the fish and open the door to secondary infections. Condition tap water thoroughly before every change.

What does the Spotted Shovelnose Catfish eat?

The spotted shovelnose is a strict carnivore in both the wild and captivity. In natural rivers it ambushes smaller fish and aquatic invertebrates; in the aquarium it should be fed a varied diet of meaty, sinking foods:

• Whole prawns and mussel (supermarket seafood, rinsed) — a staple for adults.
• Earthworms — excellent nutritional variety and eagerly accepted.
• Large carnivore pellets or sticks — useful for training and as a consistent base.
• Occasional other seafood — whitebait, squid pieces, freshwater crayfish.

Avoid feeder fish. Goldfish and other feeder species carry a high risk of introducing parasites and disease, and a diet of goldfish specifically creates a thiaminase problem that degrades the fish’s health over time.

Juveniles can be fed daily in small amounts. Adults do well on every two to three days — overfeeding is a water-quality hazard in large-predator tanks. Feed after lights-out when possible to match natural activity patterns.

How does the Spotted Shovelnose Catfish behave — and what are good tank mates?

The spotted shovelnose is rated semi-aggressive, but the key driver of that rating is size: it is an opportunistic predator that will consume anything that fits in its wide, underslung mouth, including fish it has cohabited with harmlessly for weeks if they grow slow relative to the catfish. The rule is simple — every tank-mate must be too large to swallow at the catfish’s current size and at its adult size.

Within that constraint, the species is not actively antagonistic toward similar-sized fish. It generally ignores tank-mates it cannot eat and stakes out a bottom territory it will defend by posturing rather than serious fighting. Multiple spotted shovelnose catfishes can sometimes be maintained together in very large systems where territories do not overlap, though this increases bioload dramatically.

Suitable companions include large, robust South American species: silver arowana, giant gourami, peacock bass (with caution around size differentials), oscar cichlids, and large plecostomus species that hold their own and occupy different niches. Avoid anything small, slender or slow — they will not survive long.

For a full compatibility breakdown, see Spotted Shovelnose Catfish tank mates.

How do you tell male from female Spotted Shovelnose Catfish?

Sexual dimorphism in Hemisorubim platyrhynchos is not reliably visible under normal aquarium conditions. There are no consistent external markers — males and females have the same colouration, fin shape and proportions. A mature female may appear noticeably deeper-bodied when gravid (carrying eggs), but this is an inconsistent and seasonal cue. Outside of breeding condition, accurate sexing is essentially impossible without invasive methods such as endoscopy or hormonal assay — neither of which is practical for the typical hobbyist. For most keepers, sexing this species is not a meaningful concern since captive breeding is extremely rare.

Can Spotted Shovelnose Catfish breed in captivity?

Captive breeding of Hemisorubim platyrhynchos is rated Very Hard and has been achieved only rarely, almost exclusively in commercial or specialist research contexts with hormonal induction. Wild fish are river spawners that respond to complex seasonal cues — flooding triggers, long-distance migrations and precise temperature and water-chemistry changes that are very difficult to replicate in any aquarium.

A hobbyist keeping this species should not realistically expect to breed it. The priority should be providing excellent long-term husbandry: stable water, proper diet and a suitably large environment. If captive breeding is an objective, research hormone-induced spawning protocols used by commercial Amazonian catfish producers and consult specialist literature; it is beyond routine aquarium practice.

What diseases affect the Spotted Shovelnose Catfish?

Large pimelodid catfishes are generally hardy when water quality is maintained, but a few problems are worth watching for:

• Ich (White Spot Disease): Small white cysts on skin and fins. Triggered by temperature drops and stress. Prevention: stable temperature, quarantine all new fish before introduction.
• Bacterial infections and body sores: Open wounds or ulcers often trace back to rough handling, sharp substrate abrasions or fighting injuries. Prevention: smooth substrate, avoid overcrowding, gentle netting technique.
• Columnaris (saddle-back disease): Pale patches or fraying around the dorsal area. A water-quality and stress disease. Prevention: consistent clean water and low-stress environment.
• Internal parasites: Wild-caught specimens commonly arrive with internal worm loads. A reputable supplier should have pre-treated fish; if in doubt, consult a fish-specialist vet before introducing a new animal to an established tank.
• Barbel erosion: Deteriorating or shortened barbels signal chronically poor water quality or abrasive substrate. Prevention: fine sand substrate, low nitrates, frequent water changes.

Health note: medication dosing and specific disease diagnosis are outside the scope of a care profile. Catfish are known to be more sensitive to some chemical treatments than scaled fish — always verify a medication is safe for scaleless catfishes before use, and consult a fish-specialist veterinarian or reputable aquatic health resource for sick animals.

How long does a Spotted Shovelnose Catfish live?

A well-cared-for spotted shovelnose catfish can live 10–15 years in captivity. This long lifespan is one of the most important facts a prospective keeper should absorb before purchase: this fish is not a short-term project. Juveniles sold at 10–15 cm (4–6 in) in fish stores will grow steadily for several years before reaching full size, and the tank infrastructure you commit to on day one needs to serve the fish for over a decade.

Consistent water quality, appropriate diet and a suitably large environment are the main determinants of longevity. Fish that are kept in undersized tanks, fed poor diets, or subjected to unstable water age faster and show it — growth slows, colouration fades and immune function deteriorates. Give this species the space and care it warrants and it will remain a centrepiece of an impressive system for well over a decade.