All i know is the columbian cats are born in fresh water and slowely migrate to brackish... perhaps it can be done a little faster.. but this is how i would do it for safe reasons..The Columbian Shark has been a popular aquarium species for a long time because of it's interesting appearance and peaceful disposition. Like many aquarium fish, the Columbian Shark is sold under a variety of names including: Colombian Shark, Black Fin Shark, Silver Fin Shark and Jordani Shark. Catfish like the Columbian Shark who exhibit a "shark like" appearance have always been popular with tropical freshwater aquarium hobbyists. Despite their common name, Columbian Sharks are a species of tropical catfish and act as a typical catfish does. They will generally consume a large variety of foodstuffs and spend much of their time in the middle to lower areas of the aquarium searching for leftover foods or plant matter on which to feed upon. An interesting fact about the Columbian Shark is it's ability to live in freshwater, brackish and saltwater environments if transitioned slowly. In the wild they live in each of these environments at different times of their lives and can live in each type of aquarium setup if acclimated slowly.
Columbian Sharks are a peaceful species of catfish, but they do grow to about 10 inches in size and can become dangerous to very small fish and invertebrate species. It is best to keep them in larger community aquariums with plenty of room to accommodate the large size of fish and with tank mates that are not too small as to be confused as food. Their natural environment ranges from freshwater to brackish water with some time spent in saltwater as well. It is best to keep them in either freshwater with added aquarium salt of 1 tablespoon per 5 to 10 gallons of fresh water or in brackish water with a specific gravity of around 1.005 to 1.010. It is also important to maintain constant warm water conditions (above 76° F) as the Columbian Shark does not tolerate cooler water conditions very well, which can lower it's immune system and make it more susceptible to disease. Their natural habitat has plenty of plants and rocky areas, thus it is best to replicate this in the aquarium as well. Plants and rocks should be spaced out enough to account for the size of adult specimens, leaving them plenty of room to swim about.
The Columbian Shark like other catfish species is a scavenger and will eat a variety of foods from both the water column and aquarium substrate. While they will consume leftover foodstuffs that reach the bottom of the aquarium during feeding, Columbian Sharks should also be fed sinking foods like pellets. They should be fed a variety of foods that include both meaty and plant materials in order to provide all the vitamins and minerals needed to maintain a healthy immune system. It is best to feed them 1 to 2 times per day the amount of food that they will consume within about 5 minutes time. As they mature and grow in size, the Columbian Shark will also consume small fish species like Neon Tetras and other similarly sized species.
