Bagridae (naked catfishes)

Siamese Catfish

Pseudomystus siamensis

Pseudomystus siamensis, known by the common names Asian Bumblebee Catfish, Siamese Orca Catfish, or simply Siamese Catfish, belongs to the Bagridae family. This small and rather attractive Asian catfish has no special requirements for keeping conditions and gets along well with most medium and large-sized fish. The only feature worth noting is its predominantly carnivorous diet.

Tank
from 100 L (26 gal)
Temperature
20 – 26 °C (68 – 79 °F)
Size in aquarium
12 – 15 cm (4.7 – 5.9 in)
Acidity
pH 5.8–7.8

Dangerous to small fish

Natural rangeRange on the map
  • Mekong River Basin
  • Cambodia
  • Laos
  • Thailand
  • Vietnam

Tank conditions

Plan the tank stocking
Temperature
20 – 26 °C (68 – 79 °F)
Water pH
Slightly acidic (5.8) – Slightly alkaline (7.8)
Water dH
Soft (5) – Very hard (25)
Water salinity
no salt (freshwater)
Size in aquarium
12 – 15 cm (4.7 – 5.9 in)
Lifespan
6 years
Temperament
Semi-peaceful dangerous to smaller ones
Toward small fish
a risk to small fish
Required aquarium volume
from 100 L (26 gal)
Lighting
dimmed
Substrate
soft silted
Water flow
weak
Feeding
Sinking (meat / protein)
Keeping
Both solitary and in group flexible
  • Lifespan. A lifespan to expect under good care, not a measured value: it depends heavily on tank volume, water quality and diet — and for selectively bred forms, on their origin as well.
  • Toward small fish. Based on the Predators category in the catalog or the temperament in the species parameters. “A risk to small fish” means the species is not a predator by habit, yet will swallow any fish that fits in its mouth.
  • Required aquarium volume. This is a husbandry recommendation, not a measured value: the volume depends on the keeping mode (both solitary and in group (flexible)), footprint, decor and tank mates.

Care and keeping

Description

Adults can reach a length of approximately 15 cm. Their coloration is predominantly dark, chocolate-brown, with characteristic several vertical and diagonal yellowish stripes. This pattern feature served as the basis for one of its common names — "bumblebee catfish." Sexual dimorphism in this species is weakly expressed: males are distinguished by brighter and more contrasting coloration, while females usually appear somewhat stockier than their partners.

Habitat

Its natural habitat is the extensive Mekong River basin, one of the largest in Southeast Asia, stretching across the territories of modern-day Thailand, Laos, Cambodia, and Vietnam. The catfish prefers waters with a slow current, finding refuge among submerged trees and their roots. During the day, it usually hides in secluded places, emerging to forage at night.

Behavior and Compatibility

Provided there are no very small fish in the aquarium, there will be no compatibility issues with other species. The catfish gets along perfectly with large and medium-sized cyprinids, peaceful cichlids, and many others. However, intraspecific competition for territory can occur, and if there is insufficient free space, skirmishes between individuals may arise.

Care and Maintenance

For keeping a single catfish, an aquarium of at least 100 liters is required. Given its shy and nocturnal lifestyle, dim lighting and the presence of various shelters such as snags, ceramic pots, or sections of plastic pipes are preferable for decoration. If keeping several catfish, it is important to provide several zones with shelters so that each individual can establish its own territory. The substrate can be any soft type; plants are not an essential element, but if desired, shade-tolerant and unpretentious species, as well as mosses, can be used. When placing equipment, ensure that heaters are away from shelters and not directly inside them to avoid accidental overheating of the catfish. Otherwise, the Asian Bumblebee Catfish demonstrates high unpretentiousness and adaptability to various water conditions, being found in nature even in brackish systems.

Diet

This species is carnivorous, and in a certain sense, it can be considered a miniature predator. The Siamese Catfish actively hunts small fish, aquatic insects and their larvae, as well as worms and crustaceans. In an aquarium environment, it can be accustomed to consuming fresh meat products and frozen foods, such as freshwater shrimp meat, mussels, small pieces of white fish, or earthworms. However, feeding with meat from warm-blooded animals should be avoided, as it is poorly digested and can lead to digestive problems. They must not be fed mammalian or avian meat: the lipids it contains cannot be properly metabolised by the fish and lead to excess fat deposits and even organ degeneration.

Breeding and Reproduction

In natural conditions, the breeding season coincides with the onset of the rainy season, when significant changes in water composition occur, which serves as a stimulus for spawning. In an aquarium environment, recreating these natural cycles without the use of hormonal injections, which are used in fish farms, is practically impossible.

Diseases

The main cause of health problems in these fish is an unsuitable habitat. At the first signs of illness, water parameters should be checked immediately to ensure there are no high concentrations of harmful substances (such as ammonia, nitrites, nitrates, and others). In case of deviations, the parameters must be normalized, and only then should treatment begin.

How to choose

When choosing a Siamese Catfish, attention should be paid to the fish's activity in the evening, as it is a nocturnal species. A healthy individual should have a clear, contrasting pattern without skin damage, as this species has no scales and is sensitive to external injuries. Avoid specimens with signs of emaciation, sunken flanks, or damaged fins. In the store, it is important to clarify whether the fish shows excessive aggression towards its conspecifics and to ensure there is no white film or ulcers on the body, which may indicate bacterial infections due to improper keeping conditions.

Compatibility

There are no pair reviews for this species yet — check tankmates in the matcher.

All tankmates

Plants and this fish

Matching water does not mean the plant will stay intact.

Frequently asked questions

The essentials: size, tank volume, water parameters and care

How big does Siamese Catfish get?

An adult reaches 12–15 cm in length. Plan the tank around the maximum size: the fish quickly outgrows a cramped setup.

What size aquarium does Siamese Catfish need?

The recommended volume is 100 L. A smaller tank speeds up nitrate build-up and raises stress levels.

What water parameters does Siamese Catfish need?

Temperature 20–26 °C, pH 5.8–7.8, hardness 5–25 dGH. Stability matters more than exact values: sudden swings are harder on the fish than a small deviation from the ideal.

How long does Siamese Catfish live?

Around 6 years when kept properly. Lifespan depends directly on tank volume, water quality and a varied diet.

Is Siamese Catfish aggressive?

Temperament: semi-peaceful (dangerous to smaller ones). Not a predatory species, but small fish that fit in its mouth will eventually be eaten.

How many Siamese Catfish should be kept together?

Recommended setup: both solitary and in group (flexible). Ignoring this is a common cause of stress and disease.

What does Siamese Catfish eat?

Diet type: sinking (meat / protein). Feed small portions that are finished within a couple of minutes — overfeeding does more harm than underfeeding.

What is the scientific name of Siamese Catfish?

The scientific name of the species is Pseudomystus siamensis, family Bagridae (naked catfishes). It also appears in the literature as: Leiocassis albicollaris, Leiocassis bicolor, Leiocassis siamensis.

Similar fishes

Matched by family, categories and overlapping keeping conditions

Reddish Mystus Catfish

Reddish Mystus Catfish

Mystus nigriceps

Bagridae (naked catfishes)

The Reddish Mystus Catfish, scientifically known as Mystus nigriceps, belongs to the Bagridae family, or naked catfishes. This fish has long been popular with aquarists, although until the 1940s it was often mistakenly…

Striped Mystus

Striped Mystus

Mystus vittatus

Bagridae (naked catfishes)

The Striped Mystus, scientifically known as Mystus vittatus, is a member of the Bagridae family. Its habitat range is wide, covering South Asia, including Pakistan, India, Sri Lanka, Nepal, and Bangladesh. This fish can…

Hemibagrus wyckii

Hemibagrus wyckii

Hemibagrus wyckii

Bagridae (naked catfishes)

Hemibagrus wyckii, also known as the Asian Redtail Catfish, belongs to the family Bagridae, commonly known as Bagrid Catfishes. Although juveniles can occasionally be found for sale, their acquisition is not…

Two-barbel Glass Catfish

Two-barbel Glass Catfish

Kryptopterus bicirrhis

Sheatfishes (Siluridae)

Kryptopterus bicirrhis, known as the Two-barbel Indian Glass Catfish, belongs to the family Siluridae (Catfishes). It is not commonly found in aquariums, although the name "glass catfish" is sometimes mistakenly applied…

Other scientific names and conservation status

Other scientific names
Leiocassis albicollaris, Leiocassis bicolor, Leiocassis siamensis, Liocassis brashnikowi, Liocassis siamensis
Categories
Catfish
Conservation status
Least concernLC