Blue Guarami killing other fish

Question
I have a 30 gallon tank that had 2 long finned tetra's, 2 dalmatian molly's, 2 black and 1 white molly, a beta, a red guarami, a cat fish, a large placo and a blue guarami. The first blue guarami I got died for unknown reasons, but I had no trouble with it being aggressive. After he died I purchased another one and put him in the same tank. It's been a week now and tonight it killed a tetra and I noticed one of the black molly's was wounded. I thought it was a fungus so i cut off the tank to add med. to it. When the light was out the guarami killed that black molly and when i cut the light back on it was starting on the other black molly. Do i need to move the blue guarami into its own tank or do you have other suggestions?

Answer
Hi Sabrina,
Its a shame the gourami did that. Sometimes they can be very aggressive. The best thing to do is to remove the fish into his own aquarium. You could always try keeping him separated for awhile and re-arranging the tank and then returning him a few weeks later. That way he'll be new in the tank and it won't be his territory anymore.

Best wishes and I hope this helps!
Karen~