Agressive gourami

[mtrel]

I've had a pair of blue gouramis in a 75 gallon tank for about 5 weeks now. Up until yesterday they were peaceful enough but yesterday the smaller of the two started attacking the larger one. The large one doesn't have much left in him. He's kind of floating near the top of the tank or resting on the sand. Once I even found him stuck to the filter intake. I imagine my next coarse of action is to isolate one of them. I'll pick something up tomorrow since I have nothing to use at the moment. Hopefully the poor guy will make it another day. Should I be isolating the aggressor or the victim in this case? What would cause the smaller one to suddenly behave this way? I added 2 Dwarf gouramis to the tank just over a week ago. The smaller blue is picking on them a little but not enough to cause any harm. Is there any way to correct this behavior or does one have to go back to the store?

[Zagz]

I would QT the victim so that you can treat him with some meds if necessary. Gourami's in a tank together is hit and miss IME. They have aggressive natures and can be difficult to house in the same tank. You may in the end result have to rehome one of the gourami's, as this is natural behaviour for them. Dwarf gourami's are the same.

[cogburn]

preaching to the choir here... i had 4 gouramis... one killed the smaller of the 4... the other got aggressive... 2 are dead 2 went back to the lfs... if youre going to have gouramis u either have to have only one big one... or a couple of dwarves... its hit or miss with gouramis i guess... theyre cool to look at but ive now found theyre difficult fish to keep...

[mtrel]

We'll the Gourami didn't make it through the night. I'm starting to think that it was sick and the other fish was just giving it a hard time because it was weak. Is this possible? There was really no sign of physical abuse. No nipped fins or anything. The fish appeared very fatigued and the smaller gourami would come up and poke at it every few minutes. So far the fish that was aggresive is not going after the other fish. Now the two dwarf gouramis seem to be going at it a little more but still nothing to worry about.

[Sharkrocket72]

Ive had gouramis before as well and eventually they would become aggresive. Once they would get comfortable with the tank a dominant gourami would stake his claim on the tank and bully the others. I never had any die from it but he would chase the others and make them stay hidden while he swam around.
Sorry to hear you lost one.

[Zagz]

Sorry for your loss.