his month we welcome back regular contributor and writer for the U.K. magazine 'Practical Fishkeeping', Chris Ralph, with another feature on his favourite topic " The Big and Nasty" with an indeph look at the Devil Catfish from the Indian continent, Bagarius bagarius. I will let Chris carry on and hopefully educate and entertain you.

Bagarius bagarius is commonly known as the Devil Catfish, which is also referred to as Bagarius yarellii.
This catfish is quite a rare find amongst shipments of fish from Asia. Bagarius bagarius belongs to the family Sisoridae which are more commonly referred to as Asian Hillstream Catfishes. Within this group of catfish there are around 23 genera and 85 species. As their family name suggests they are naturally found in the fast flowing freshwaters of southern Asia. Most of the catfish within the family Sisoridae are small to medium in size from 6-30cm, with the exception of Bagarius with representative species growing in excess of 2 metres!

Bagarius are described as predatory fish quite unlike the other members of the family Sisoridae which tend to be omnivorous. In its natural habitat Bagarius will live under bogwood or logs in fast flowing rivers in wait of its next victim. All of the Hillstream Catfishes are able to inhabit mountain streams by virtue of the fact that the skin on the undersides of their bodies is adapted by being corrugated thus acting as an adhesive attachment to rocks and stones. In addition to the skin being corrugated or folded another factor making these fish better able to withstand the strong water currents they have flattened heads. It is generally documented that most of the representative species of sisorids have a ventrally positioned mouth, allowing them to rasp algae from the substrate (which is not the case with Bagarius bagarius).

I have personally been looking after (above) one of these magnificent catfish for the past year now and am just waiting for its owner to collect it before it outgrows its present accommodation. I am quite a fan of large catfish as I am sure that those of you who know me appreciate, the problem being the eventual size that this fish can attain…I really cannot accommodate a fish that might eventually grow to 200cm (or around 79" in old money).

That said I am pleased that I have been able to observe this fish over the last few months. This fish has evil written all over its face, it watches every move that I make whilst in the fish house, and no matter where you are you can sense this fish watching you. It is a fish that does not like to be watched whilst it feeds, so you have to try to be out of eye-shot in order to see it feed. Very much a predator in its natural environment, it will however, take dead foods in captivity. At present this fish eats almost anything on offer including cockles, whole prawns, mussels, dead fish and large earthworms. It is for this reason that this catfish leads a solitary life, as I would not risk housing any other fish with it.

When keeping the Devil Catfish it is essential to provide the fish with oxygen-rich water due to the fact that these fish are from highland streams. I have personally found it essential to provide good filtration and water movement in order to keep this fish in optimum condition. Regular 25% water changes are also appreciated by this catfish, and I always carry these changes out weekly and certainly no longer than fortnightly.

Other water parameters such as pH and hardness are not as important as good water circulation and aeration, but nevertheless are still of importance. I have found that this catfish will tolerate lower water temperatures than most other species of catfish due to the fact that its natural environment is cooler. At present the Bagarius that I have is kept at around 22ºC.

I have to admit that this is a magnificent catfish to observe, but be warned that they will eat anything small enough to fit inside the enormous mouth that they possess. Finally perhaps it is just as well that these fish are rare amongst catfish imports, as in the wrong hands it could do untold damage to other fish and rapidly outgrow small accommodation.