The Wels Catfish is a massive, highly predatory freshwater fish native to Eastern Europe and parts of Asia. As one of the largest freshwater fish in the world, it is wholly unsuited for standard home aquariums and requires a heavy-duty heated indoor pond or massive custom setup. They are highly opportunistic predators that will swallow any tank mate that fits into their enormous mouths.
Wels Catfish (European Catfish) At a Glance
Wels Catfish (European Catfish) Tank Requirements
Will Wels Catfish (European Catfish) fit in your tank?
Care guides tell you what Wels Catfish (European Catfish) needs, the next question is whether your tank can safely provide it. Test Wels Catfish (European Catfish) against your tank size, maintenance needs, and the fish you already keep before you buy.
Useful setup supplies
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Wels Catfish (European Catfish) Water Parameters
Water care products
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Wels Catfish (European Catfish) Temperament & Compatibility
Wels Catfish (European Catfish) Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Adult / Standard
The standard adult form. Requires an indoor pond or massive custom public-style aquarium.
Same care requirements as the base species
Also known as: Wild Type Adult, Full Grown
Juvenile (Grow-out)
Juvenile Wels Catfish frequently sold in the monster fish trade. They grow exceptionally fast and will quickly outgrow standard aquariums. Should only be purchased by those with concrete long-term pond solutions.
Differs in 3 traits from base species
Also known as: Baby Wels, Cub
Albino Wels Catfish
A highly popular color morph in the monster fish keeping hobby. Features a pale yellow/white body with pink eyes. Retains the exact same massive size and care requirements as the wild type.
Same care requirements as the base species
Also known as: Albino, Golden Wels
Wels Catfish (European Catfish) Care Guide Summary
The Wels Catfish (European Catfish), scientifically known as Silurus glanis, belongs to the Catfish family group. Adults reach a maximum size of approximately 150 cm and have a depressed body shape with a fast growth rate. Classified as aggressive, this species primarily occupies the bottom zone of the aquarium and produces a extreme level of biological waste.
To thrive, the Wels Catfish (European Catfish) requires a freshwater only aquarium with a minimum volume of 10000 litres and a tank length of at least 400 cm. Water temperature should be maintained between 4°C and 25°C, with a pH range of 6–8 and a general hardness of 5–20 dGH. A moderate water flow is preferred.
Due to its specialist needs, the Wels Catfish (European Catfish) is best suited for fishkeepers who can provide a carefully planned setup. This species is available in 3 varieties: Adult / Standard, Juvenile (Grow-out), and Albino Wels Catfish. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Wels Catfish (European Catfish) Habitat Setup
When setting up an aquarium for the Wels Catfish (European Catfish), a moderate water flow best suits their natural preferences. Because this species occupies the bottom zone, the aquarium layout should prioritise sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include smooth gravel or rounded substrate to protect their sensitive barbels and driftwood, which can serve as both a hiding place and a dietary supplement.
Wels Catfish (European Catfish) Compatibility Notes
Classified as aggressive, the Wels Catfish (European Catfish) is best housed alone, as they do not tolerate others of their kind in confined spaces. When choosing tankmates, any fish small enough to fit in its mouth will likely be eaten and territorial behaviour may cause issues if hiding spots or floor space are limited. Selecting tankmates that favour different water layers from the bottom zone can help reduce competition and territorial overlap.
Wels Catfish (European Catfish) Feeding & Diet Considerations
The Wels Catfish (European Catfish) is a predatory species that will readily consume small fish, so nano or bite-sized tankmates should be avoided and is primarily active at dusk and dawn, so offering food shortly after lights-off ensures it receives adequate nutrition.
Feeding products
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Frequently Asked Questions About Wels Catfish (European Catfish)
How big does Wels Catfish (European Catfish) get?
Wels Catfish (European Catfish) (Silurus glanis) typically reaches a maximum adult size of approximately 150 cm. They have a depressed body shape and a fast growth rate.
What tank size does Wels Catfish (European Catfish) need?
A minimum aquarium volume of 10000 litres and a tank length of at least 400 cm are recommended for Wels Catfish (European Catfish). This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Wels Catfish (European Catfish) need?
Wels Catfish (European Catfish) thrives in freshwater only conditions with a temperature range of 4–25°C, a pH between 6 and 8, and a general hardness of 5–20 dGH. A moderate water flow is preferred.
Is Wels Catfish (European Catfish) peaceful or aggressive?
Wels Catfish (European Catfish) is classified as aggressive with an aggression score of 8 out of 10. Careful tankmate selection is essential to avoid conflict.
Can Wels Catfish (European Catfish) live with others of its kind?
No. Only one Wels Catfish (European Catfish) should be kept per tank. Keeping multiples in the same aquarium typically results in aggression and stress.
Does Wels Catfish (European Catfish) have any special tank requirements?
Yes. Wels Catfish (European Catfish) benefits from smooth gravel (sensitive barbels) and driftwood (digestion/hiding) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Plants That Suit Wels Catfish (European Catfish)
These plants pair well with Wels Catfish (European Catfish) based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
African Onion Plant
Crinum calamistratum
Afzel's Anubias
Anubias afzelii
Amazon Sword
Echinodorus amazonicus
Anubias Barteri
Anubias barteri
Ashy Pipewort
Eriocaulon cinereum
Balansae
Cryptocoryne crispatula
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