Hi there.

All of excitement in my new flat, I decided to go out and buy some
fish to make it nice in there, although it's something I've been
thinking about for a few months now. I am a total neophite in the fish
business, I basically asked the guy at the store for the right stuff
to keep two fish happy. He gave me some flakes, some stuff that
de-chlorinates tapwater, a 3 gallon tank, gravel, a nice little ruined
building, and two teeny fish (about an inch long each): one standard
goldfish and one comet.

They seemed happy enough the first couple of days, but now the comet
(Rudi) has taken to chasing the common goldfish (Carlos) around the
tank, stealing his food, and nibbling his fins. The fin on the bottom
of Carlos towards the rear is shredded now, and he really can't be too
happy about it.

What's causing this? Is it just an aggressive fish? Is the tank too
small? Or is it some kind of mating behaviour? Will it stop? Or is
Rudi going to hound Carlos until he's dead?

Any help you can give would be gratefully received.

Thanks,

Keith.