why is my little fish nibbling my big fish?

Question

I have a goldfish which we have had for 5 years. He started off black and is now a goldfish orange colour. He has grown massivly in the last few years and is now approx 7 inches long!!

We have recently been given a fantail which is tiny. and the fantail is nibbling the bigger fish. Why?

Also, several of the other fish have turned a pink colour - why?

Thanks

Emma

Answer 1

Sounds like they are just getting to know each other a bit. This process can take several days to a week. Usually no significant damage is done, but there are exceptions so continue to watch them carefully. If it doesn't stop the only course of action is to seperate them.

MM

Answer 2

Goldfish will swallow small fish. Small fish (including small goldfish) that cannot be swallowed by bigger goldfish will bully the goldfish. Do not take the risk, separate them immediately. For me I don't want my big goldfish hurt. Each goldfish has its own character. If they are compatible, they should be compatible from the beginning.