2 questions about goldfish

Thanks fantail. Redtailcat, I'm afraid I can't follow your advice because my tank is already on the verge of being over-crowded, but thanks for your input.
 
My comets chase my fancies and my fancies(especially black moor) chase my comets mainly after feeding but I think it is whenever they are bored. No one gets hurt, they know when to get out of the way. Maybe it is just their way of playing. How do we know? As long as no one is getting hurt I'm not going to worry about it.
 
I have just Comets in my tank and they like to chase eachother sometimes. As long as it doesn't come to fin-nipping, it is just their way of playing. When they are courting (getting ready to mate) there is a little chasing involved and some nosing. The male usually gently pushes the female with his nose and she will let him nudge her if she is willing to mate. If not she will just swim away. After a while he will get the hint. Because you have a common and a fancy, I would tend to believe that it isn't mating but just some playing, maybe a little competing for food. They LOVE to eat A LOT.
 
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