Problem With Aggressive Gourami

[720510]

Hi

I have 2 medium sized Angels, a group of tiny swordtails and one med Golden Opaline Gourami, and a recently added smaller sized blue Gourami (not sure of the exact type, but it's blueish in colour.)

The tank is more than a year old and well cycled, and now quite nicely planted. CO2 is added through sugar/yeast combination.

Initially, he was ok, but as of late, he is very aggressive, and is chasing around not only the other Gourami, but also the Angels! (Much bigger than him). He is clearly healthy, as he is constantly swimming and eating well.

As a result, he has claimed one half of the tank all to himself, with the rest of the fish all squatted up on the one side.

What could cause this aggressive behaviour?

Any ideas?

Thanks

 

[Davo86]

Hi

what size is the tank?, what size size is the gourami? do you know if they are both male? is the new gourami the same shape as your gold or is it a dwarf gourami?

It does sound as though the gold three-spot gourami is maturing and is starting to show the territorial behaviour that comes with this.

 

[benniebru]

yea they can be aggressive, a while ago i had a blue gourami that would kill any other gourami that was in there with it, but left any other fish alone

 

[720510]

The tank is Fluval Duo Deep 800 tank, 125L.
They are different, and I suspect both male. One is gold, one is blue. The blue one is about half the size of the gold one.

 

[Davo86]

you probably have a gold three-spot and an opaline three-spot gourami which are really the same species but different colour morphs, if they are both male three-spot gouramis then i'd say your tank is too small for you to successfully keep both.

pics of an opaline and a dwarf.

opaline gourami

dwarf gourami

 

[720510]

opaline gourami

Thanks. The second one (the problematic one) looks exactly like this pic so that's it then.

I'll take it back to the LFS tomorrow.

Thank you for the replies.

 

[Biulu]

you probably have a gold three-spot and an opaline three-spot gourami which are really the same species but different colour morphs, if they are both male three-spot gouramis then i'd say your tank is too small for you to successfully keep both.

In itself the tank is not too small for 2 opalines; you need around 30 litres for each gourami. HOwever, much depends upon the decor (do you have enough hiding places, plants etc. to allow for territory making?), and also the gourami. Yes, sometimes you will get an extremely agressive one which will claim a larger territory.

What sometimes helps is to change the decor around when you put in your new fish. However, seen the fact that this one was added last, it probably wouldn't have made a difference in this case.