Which fish are good tankmates for Columbian Shark Catfish?

[Aliyo]

I have 2 Columbian SHark Catfish each bout 6 inches in length. I was wondering if i should get some more shark catfish to accompany them because i heard they like to be in groups. About how many would be appropriate?
And what other fish could peacefully live with them? I want to get some nice fishmates that would add color to the tank...
And how should i set up their tank? My tank is kinda empty now... What kind of environment and surroundings do they like?
Any answers would be much appreciated... THanx...

[Mantra]

Colombian Shark Catfish are very similar to South American Pimelodids, keep with fish that like similar water conditions and are big enough to prevent being considered prey. Youngsters (smaller than 12cm) can be kept in alkaline fresh water (with for example rift lake cichlids), but larger fish MUST have salt added to the water in order to thrive.

Suggested Tankmates Initially most medium sized active fish, but with the addition of salt to the water as the fish grow, brackish water fish such as Monos, Scats or large Mollies are the order of the day.

Go through this article for some more details:
http://www.planetcatfish.com/cotm/cotm.php?article_id=63

[Barb R]

Colombian shark catfishes are big, powerful looking animals with sleek silver bodies and active natures. Although distinctly predatory, they are not aggressive and on the contrary, can be bullied by fishes like cichlids. In the wild, they live in fresh and brackish waters, and sometimes enters the sea. In the aquarium: hard, alkaline water is critical, as is a powerful filter and good oxygenation. A specific gravity of 1.005 to 1.015 is about right, with regular fluctuations within this range being beneficial to health. They need a big, roomy tank with a powerful motorised filter.

Both sexes reach about 12 inches in length, but females are noticeably stockier and develop swollen pelvic fins when mature.

Colombian sharks appreciate a dark aquarium with a definite current. Decorate the tank with a thin layer of sand or gravel for burrowing in, with large rounded boulders to make caves and lairs. Keep in schools of three or more. Small specimens are adaptable, but above 4 inches, they become distinctly restless, perhaps feeling some migratory drive. Fluctuations in salinity and strong water turnover are essential at this stage to settle the fishes down. Compared with other catfishes, these fish are not nocturnal and swim constantly, often into a part of the tank with a steady flow.

Shark catfishes are so named because of their powerful, sleek shape. They swim gracefully, something not easily appreciated in a small tank. Colombian sharks have venom glands in the base of the dorsal fins, and should therefore be handled with care. They also possess glands in the mouth capable of secreting anticoagulants, which they use when hunting. More obvious to the aquarist are the continual drumming noises they make. These are possibly used for echolocation and for communication between fishes in the school.
The name Arius signifies that the fish is ‘of the war-god Ares’ not altogether unfitting considering their impressive adaptations to the predatory lifestyle! All in all these are fascinating fishes.
Eventually, these catfish will eat anything they can put in their large mouths. They are predatory catfish...not the normal scavenger. A school of them alone can be impressive though.
The fish need to be acclimated into saltwater eventually. So during the brackish age, some people have puffers in the tank. As they get older (when they'd head out to sea), they should be put into a 72" long saltwater aquarium (slowly acclimated of course!) and you can start adding the VERY colorful saltwater fish. Porcupine puffers and triggerfish do well with your sharks.