Very nice and very tame. Get a powerful filter as they like to spend most of their day swimming against the current. When I bought them they came to me at about 4 cm long and grew fast. I advised my mom not to place the neon tetras in the tank with them, but she did anyways. She had 10 and now only 3 remain. They are very playful and enjoy giving the guppies a chase from time to time. I mostly feed them blood worms and flake food.
These are beautiful catfish, and when young, I have noticed they school tightly, but start to squabble a bit with age. They're often listed as brackish, but they're doing just fine in my african cichlid tank. Very active, shiney, and never stop moving! Startle very easily, though, and I have noticed them almost jumping out of the tank a few times.
I have to agree with Barbara Dobson, Mack the Knife is appropriate. After 3 unsuccessful attempts at keep one of these nifty little fish alive, I got one to live past the 1 week live or die period after coming home from the local pet store. I have had this cat for 6 months and has grown rather fast to 13 or 15 cm long. I too have noticed the disappearance of all of my other smaller fish, neons and other tetra type snacks. My larger fish like Buenos Aires Tetras and Algae Eater, etc., are doing fine. The final bit of evidence when I saw him/her swimming around proudly with a half of a fish in its mouth.
A truly amazing fish! I have only one Colombian cat, but it has impressed me in many ways. It acclimated from fresh water to brackish to marine in about 4 months. I originally bought it for a 110 L brackish tank. Later, I decided to change the tank to a freshwater tank, so I put many of the larger fish into a 475 L marine tank. The catfish, along with a mono, a moray, a freshwater lion, and an archerfish, have been living in this tank for about 9 months now, and thriving. He never molests two slightly smaller gobies, and often diffuses territorial squabbles between them by investigating the commotion they cause. It is a very enthusiastic eater. I've observed my 15 cm specimen downing as many as 6 large pieces of krill in one feeding, its belly bulging dramatically. From pet shop experience, I've found them to be succeptible to contracting Ich, but, once established in a tank, seem to tolerate and recover from it well. A side note: I've seen Blue Channel cats sold in chain stores as Colombians. They do not tolerate more than minimal salinity.
I currently have two of these guys in a 200 L freshwater tank. The oldest one I have had for about a year and he is now 15 cm long. The youngest I've had for a couple of months and he's 8 cm. I've noticed over time that the older one has stopped eating from the top of the tank and will now only eat from the bottom. He loves beefheart and won't eat much else. The smaller one will eat just about anything at any level of the tank...flake food, bloodworms, shrimp pellets, etc. Although, he doesn't swim upside down on the top of the tank anymore looking for food, when they are very young they seem to do that constantly. As for disease, it helps tremendously for them to have plenty of room to swim in and be sure NOT to overcrowd. I have experienced Ich before with these types of sharks, but that was in a 40 L tank and I was just learning how to care for fish. They handle a wide range of pH (low or high). Having a freshwater tank has not seemed to hurt at all so far...both of my Sharks are thriving and growing at a nice rate. Keeping them well fed will also help to prevent against stress and disease. I keep mine VERY well fed! As they get older they seem to become much more territorial with their own species. Be sure to keep some hiding spaces (driftwood, etc.) as they like to hide, they will eventually become very shy and less active the older they get. You can tell a lot about this type of shark's health by their color and fins. They seem to turn a darker shade (almost black) when feeling a bit under the weather. Your more healthy Columbian sharks will be a nice shade of silver. He will also keep his fins spread wide from his body when healthy... a sick shark will pull his fins into his body and his dorsal fin will lay flat. Tankmates: DO NOT keep them with Guppies! Even the younger sharks will eat them (neon tetras too). Surprisingly though, I have been able to keep very small cory catfish (smaller than some of the eaten guppies) with them and the sharks won't even take a second look.
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