1ADAM12

About 2 weeks ago I get a phone call from my friend that says his friends tank is leaking. Well he found homes for all of his smaller fish but needed a home for the Upside Down Cat. I said I would take it. So I put it in my 45 gallon tank and it has been fine for 2 weeks.

Well I wake up this morning and he has my hatchet fish in his mouth eating it. I look in my tank and my 3 sword tails are gone, my 2 black mollies, and my small danio all vanished over night. To say the least my tank looks very empty now lol.

Is it common for these fish to be agressive? I have been feeding him brine shrimp and blood worms. He has also been eating the flake food I give my other fish. Oh yeah and he is also almost 6 inches long.

Any suggestions?

Thanks,
Adam

MousePotato

Is this an Asian upside down catfish? The big black ones? If so, I have one and I have read they will eat anything less than two-thirds of their size. Mine doesn't seem very aggressive, but then she's in with some rather boisterous tankmates. She seem partial to the African Cichlid "Attack!" pellets, but I'm sure she'd eat my clown loach if she were hungry enough! She's about 8 inches long.

1ADAM12

Yes it is the big black one! I have clown loaches as well and it has left them alone,

MousePotato

I only mentioned the clown loach because, at four inches, he is the smallest fish in my tank. They (the catfish) are carnivores and may very well feast on your other fish. I don't know that it is an "aggression" issue, but it may be a compatability issue.

I would not keep this fish in a community tank. The one I have seems fine in my setup, but I have her with large African cichlids who tend to hold their own with just about anything. A less aggressive fish would probably not stand a chance with her.

On the plus side, these are really fascinating fish and quite enjoyable to watch. Husband calls her "The Dorkfish" and loves to watch her storm around the tank like a semi driver on I-45.

1ADAM12

Thanks for your help. If I had realized it was a very agressive fish I w ould not have agreed to take it in. I think I will head up to my local fish shop and trade it in for some more peaceful fish lol

Thanks again,
Adam

MousePotato

No problem, Adam. I hope he finds a good home and you get your peaceful tank back. He would have gotten too big for a 45 gallon anyway. The females can get up to a foot long!