Nipping problem...

  • We are currently upgrading MFK. thanks! -neo
Your nitrate from their bioload will start becoming more difficult to keep down with WC, when they get to be about 7", I would guess (with 4 of them).
 
It should help but I'd try to match size. A school of adults is an amazing sight!
 
2columbians;4880536; said:
I have two Columbian Shark Catfish (3.5" each) in a 75 gallon brackish tank. One has shown dominance over the other and, in the past couple of days, I've noticed some evidence of nipping on the anal fin (which healed remarkably fast) and tail of the less aggressive cat. Is this just typical juvenile behavior that will pass with time, or will this be a long standing issue? What can I do? They'll grow too large for the tank they're in, let alone adding another to even out the aggression level. Would a couple Mollies throw them off?

But;

I have two Columbian Cats that I experienced the same issue with when they were young. However, I quarantined the dominant one & made sure the smaller one got the same or more food. Eventually the dominance did shift & now a year later the originally smaller one is still the larger/dominant. They, however, have not had any issues since. They get along VERY well...are by each other's side constantly...& show nothing but love ; ) Perhaps I am just lucky, it may be much easier to get a couple more...If I had the room I know I would! Mine did work it out though, with some coercion, so I wouldn't rule it out as an option ; )

-Kaila June
 
Interesting facts on this species:

Fish from this family, the Ariidae, have rather sensitive hearing and do not handle loud or sudden noises well at all. They may frighten from such and injure themselves or leap from the tank. Loud music is risky.

This family shares another common characteristic – the first spine of their dorsal fins is venomous. Be extremely carefully when you must have your hands in the tank. No sudden moves or noises, please. The pain or risk may be your own.

These fish are opportunistic predators – which means that if they can eat another fish or invert, they will. Due to their size and the need for keeping at least 3 as an absolute minimum school, even in a 180 gallon tank there is not sufficient room unless a substantial sump, perhaps a 120, is added to the display. Other tank mates are pretty much beyond the carrying capacity of the set up. Operating costs will be high until the setup is on the more efficient SW techniques.
 
For the most part they do get along great. There's no bullying over food at all, but at night the dominator gets a little territorial with the sweet spot of current from the power head (1050 gph). I was wondering if maturity would be a factor in their "sharing" the space... I'll continue to monitor their behavior and see how they do for a week, or so. Thanks, Kaila June, thats kinda what I was wanting to hear. Do you have any pictures? How big are they now? I love these fish!
 
If you keep checking thr reef, we get a decent sised one every few months.
 
Definitely, Dave, I've kinda got my fingers crossed in hopes that they'll grow out of it. If not, I'll be on the look out for one, or two, of about 3.5 - 4". There's a warehouse on E. Hanna that does online sales: http://premiumaquatics.com/store/merchant.mvc I called to see if they've got a store or if it's just online and the guy I spoke with said they're livestock inventory is open to the public for a couple hours on Fridays & Saturdays. Have you heard of them?
 
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