Usually it's because the male wants the breed with the female so he chases the female around the tank!
So unless you want little fry (baby goldfish) in your tank you should separate them!
no let it doing
As soon as spawning has finished she should be removed. The male will chase the female and kill her otherwise.
Goldfish of both sexes can be happily put together usually without any problems. During the breeding season male fish may chase the female but in general they are very peaceful.
Female goldfish are usually bigger than male goldfish.
the goldfish that is being chased might be a female goldfish where as the others are male goldfish, so the female one gets battered around the tank and the fins and tail might shred it is a good idea to separate the single fish so it wont be attacked. i know this cause my Goldfish do the same XD Look for white dots on the cheek of fish that r chasing the other one. if it does have white dots its a Male hope that helped :)
Goldfish are egg laying fish, and unless there is a male in the tank to chase the female and convince her to release eggs, you may not know that she is either female, or even has eggs to release.
Some goldfish are male, while others are female.
Well yes you need a male goldfish and a female goldfish to have babies but it takes allot of time to breed them.
Usually a female goldfish mates with a male goldfish!
Fancy goldfish can be male or female.
goldfish start out with female and then turn into male!!!!!!
Female goldfish are slightly bigger than males