Is a Columbian shark a bad idea?

[Jivamukta]

Hi there,

I'm quite new to the hobby, a(nd totally new to this forum) but have quickly found I'm a lover of catfish. I'm about to get a new 530litre tank in which I want to keep a variety of Synodontis spp, some Pimelodus Pictus, and a bulldog and Flash pleco in a freshwater setup. I really love the idea of a columbian shark, but suspect it may be a bad idea.

I've read conflicting reports on adult size of the columbian shark, ranging from 10" to 2 feet! I've also read conflicting reports on water requirements, some site suggesting it can live in anything from freshwater to marine, others saying it will do fine in freshwater as a juvenile, but will need brackish to marine water as it matures.

My LFS advised me that their columbian Sharks have been fully acclimatised to freshwater and will be fine, and that it only grows to 10" so will be fine in my new tank. But they said it's a shoaling species so I should buy 4 of them. I really would only want one.

Can you please give me your thoughts? I've been looking on YouTube and seen loads of videos of people keeping a lone columbian shark, but most people seem to be keeping them in brackish, and I really don't want to go down the brackish route. I don't want a fish that will out grow my tank, or a fish that is neurotic because it needs others of its kind around.

I've pretty much ruled it out, but thought I'd run it by you guys in case you think it could be a viable option.

Hope to hear from some of you soon.

[Viktor Jarikov]

Welcome to the planet!

If you want only one, that's enough reason not to get any.

Through the years I've encountered about 3-4 cases where people accidentally (to no credit to their fish keeping ability) were able to raise them into adulthood (1' or a bit over) in freshwater but all of them invariably perished soon thereafter, after a long illness and most were unbearably skittish.

These fish are born in mostly fresh water and indeed can be ok until say 4" in freshwater (harder water is better I'd imagine). Then one needs to start adding marine salt to their water, gradually over months or a year converting their water to full marine. This mimics what happens to them in the wild.

Almost no one does it. So I guess pretty much 99.9999% of the ones sold (almost every LFS carries them because they are as cute as buttons when small and they SELL!) perish because they are never transferred into brackish and then marine.

For more earnest info, see this thread and the links I provided in my post #34 here: http://www.monsterfishkeepers.com/forum ... st-6513159