Aggresive molly

[Hannah]

Hello!

One of my male sailfin mollies are very aggresive towards the other fishes. :(
I doesn't only chase his girlfriends, but the males as well.

I built a little cave in the tank, and the frightened fish started hanging out in there almost all the time to avoid him (and behind the filter, as they did before).

So two days ago I removed the evil male and put him in a tank of his own, and now the other mollies are slowly starting to leave the hiding places and swim around.

Do you think I can ever put the male back in the tank again? Would rearanging do any good?

It's no fun when all the fish are inside the cave or behind the filter all the time...

[William]

The aggressive male most likely was the dominant one.

Rearranging might help but most likely only in the short run. instead i would suggest feeding the other fish more know when the male isn't there to let them grow and become stronger so that they can stand up to the male better.

You are not saying whether you keep plants, if not I would add plants so that the sides of the aquarium are densely planted. Alternatively use roots that reach the surface to give the fishes other hiding places then the cave.

Adding other fish to the aquarium might also help. Getting some fishes that not are aggressive but stronger then the male so that he can't bully everyone. I've seen this in bettas a number of times, males that bullies everyone until they gotten badly beaten one time and then they behave much better. :P

/william

[Hannah]

Ha ha, I would really like to see that little bully get what he deserves once and for all... :)
What kind of big fish can I keep in brackish water?

I already have some plants, but the tank is not densly planted.

[Dory]

Try some puffers for the brackish water guys.. They are absolutely adoreable, but do some research on them.