HELP! Aggresive Cowfish

[seanothon]

I just added a Striped burrfish (Chilomycterus schoepfi) to my FOWLR tank and my Cowfish is not happy about it. Everything seemed normal the first day, the cowfish would chase the burr away every now and then but nothing else. Over the night the cow must have gotten ahold of the burr because he had a couple bites the next morning and when I tried to feed them the cowfish went street on him. It rushed at the burrfish, which then puffed up and that only made it a large immobile target. I broke up the fight with my feeding tongs and everything went back to normal. I tried putting a mirror up against the glass to distract the cow, which worked for a little while but the next morning the burr was beat up again. I moved the cowfish into QT and moved the rocks around in the tank. The burr is acting completely normal and still eats like a pig.

I plan on leaving the Cow out of the main tank for 4-5 days and hopefully the burr will establish its own territory. The cow is probably 8-9" and the burr is about 3"

Any other advice or suggestions?

A couple pics to show the size difference

[seanothon]

OH and the tank is a 120gl

[MrTuskfish]

Longhorns are great fish, usually very peaceful. I had one for years before moving and he never bothered anyone. I happened to have him with a spiny box, a close relative of C. schoepfi . Probably just some temporary "pecking order" stuff; maybe the cow has finally found a fish it can catch. Even the most peaceful fish can become territorial and not like new fish I'd expect it to calm down, but still watch for any sign of toxin. (very unlikley, as the cowfish is the aggressor---but sure no guarentees. It doesn't happen often, but with the potential for a toxin problem, worth some more of my drivel (IMO). Several times, in many years, I've seen very peaceful fish react to aggression by a tankmate and become nasty themselves; I won't guess why. If this should happen, and the cowfish starts becoming a victim, it may be time to QT him for a few days and then re-introduce him. Please keep us posted; I really like both of these fish and am interested in what happens---I'm betting on peace within a day or two.

[seanothon]

Longhorns are great fish, usually very peaceful. I had one for years before moving and he never bothered anyone. I happened to have him with a spiny box, a close relative of C. schoepfi . Probably just some temporary "pecking order" stuff; maybe the cow has finally found a fish it can catch. Even the most peaceful fish can become territorial and not like new fish I'd expect it to calm down, but still watch for any sign of toxin. (very unlikley, as the cowfish is the aggressor---but sure no guarentees. It doesn't happen often, but with the potential for a toxin problem, worth some more of my drivel (IMO). Several times, in many years, I've seen very peaceful fish react to aggression by a tankmate and become nasty themselves; I won't guess why. If this should happen, and the cowfish starts becoming a victim, it may be time to QT him for a few days and then re-introduce him. Please keep us posted; I really like both of these fish and am interested in what happens---I'm betting on peace within a day or two.

I'm hoping you're right. The cowfish will be put back in Saturday and right now the burr seems great.

[jjk_reef00]

I think your 9" fish has completely taken over your 4' tank. The aggression is most likely a sign that you need to upgrade before adding any more fish...

[MrTuskfish]

I think your 9" fish has completely taken over your 4' tank. The aggression is most likely a sign that you need to upgrade before adding any more fish...

I agree, I completely missed the tank size; I think some 120s are even 30" cubes.

[seanothon]

UPDATE! 3 days since the cowfish has been re introduced into the display tank and no attacks. The cow is still in charge and the burr stays out of his way but it looks like the time out of the tank helped to split up the territory

[triggerfreak]

That is good to hear.But i would seriously look into either a nice size upgrade ( to like a 150 to 250 gallon ) or getting a new home for the cow fish.He is way to big for your size tank and needs alot more room.

[seanothon]

That is good to hear.But i would seriously look into either a nice size upgrade ( to like a 150 to 250 gallon ) or getting a new home for the cow fish.He is way to big for your size tank and needs alot more room.

Yeah i'm sure your right. Just a matter of funds and a place to put one that big in my second floor apartment