I've had mine for about four years in a 180 liter aquarium. He/she (I prefer he) has survived a few moves and several power outages due to ice on the power lines. The three day outage killed my angel fish of seven years, but the irridescent shark/catfish is still with me. Needless to say he's grown a lot since the 8 cm I purchased him as. After reading the length he can reach in a larger tank, I anticipate getting one. No more moves for quite a while (I hope) and this hardy guy deserves it (he just gave me a good splash during feeding). I recommend a tank cover or they will end up on the floor (hasn't happened, but I can see it under different circumstances). He has been living with several tetra for three years not to mention a crawfish for about seven months (the crawfish went soft shell and all of them ate him...sorry, didn't know). He rearranges all decorative items in the tank to his liking no matter how nice a nook I create for him after cleaning the tank!! A great fish!
I have 5 Irridescent Sharks. I did not know they would get so big. One is 16 years old and 45 cm long. The other 4 are at least 5+ years old, 3 are 45 cm long, and the small one is about 15 cm long. They were all about 7 cm long when we first got them. They are in an 350 liter tank. The addition of a DIATOM filter seems to take care of disease problems for them. I use the added filtration every 2 or 3 weeks.
We have 2 irridescent sharks that are about 18 years old. They have gone through many cases of Ich and have bounced back to health every time. Sometimes they spaz out and have killed everything else that we once had in there, with the exception of the plecos, but only because we get the plecos when they are very small and they hide as much as possible and stay away from the sharks. They are in a 300 liter aquarium that has a top that is completely covered. However, one morning I was on my way out the door for school and couldn't figure out what my dad was doing with his arm in the tank. When I asked him, he said that one of them had hit the lid so hard that he came out and my dad found him on the couch. Somehow my dad managed to talk him into staying alive, I guess. He bounced back to health, although they are pretty scarred up from moments like these. So far, these 2 are the only ones we have ever been able to keep alive.
If you put a powerful horizontal current in the water the stress level of the iridescent shark decreases immensely. They naturally live in fast flowing rivers of Thailand and China. The appropriate home for an iridescent shark would be a 1000 liter tank with little decorations and a strong current. I have seen species over 90 cm long in zoos and over 120 cm long in the wild.
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