a killer goldfish!!!!

[fairies07]

Has anyone ever heard of a goldfish measuring 5-6" eating tropical fish,eg: guppys,noens, black mollies and sharktail mollies? We know for definate it was him as he had 1 in his mouth this morning, could anyone tell me why he done it? Also it wasn't his tank we added him to the tank. (we have taken him out now and put him back into his own tank)

[wildwood]

A goldfish that size can manage earthworms, so a few guppies and neons is no trouble. What were you thinking of putting him in there with your tropicals? He's eaten your tropicals because that is what fish do to stay alive.... eat other things when they can catch them.

Putting a goldfish in a warm water aquarium aids in making your goldfish more active and speeding up its metabolism, thus making it eat more.
I hope you have lowered the water temperature gradually when you put him back into his own tank, or you might end up with a sick.dead goldfish, dispite him feasting on your tropical fish.

[Lonnie]

Apart from the above excellent answer, Goldifish will eat almost anything, if it can fit in their mouths.

[B00]

I'm so glad you've put him back in his own tank, goldfish are coldwater fish whilst your tropicals are ummm well oddly enough tropical....lol

And yes, goldfish are known cannibals, often they'll happily have other tank mates with them until they decide that the other inhabitants would make lovely snacks- I learn this by mistake after my 'adorable' goldy ate 3 minnows that were living with him for 18 months, I was gutted!