Thank you for getting back to me, Mandy. A growth this size, and with a blood vessel in it, is most likely a tumor. The fact that it has been slowly growing over the period of a year is further evidence. There won't be any home treatment that will make the growth go away. Goldfish are prone to both benign and cancerous growths. The only way to know which this is would be to consult an aquatic vet. The vet would also be able to remove the growth. If you want to pursue this, the following link will take you to a directory of vets. Just click on a name for their contact information.

http://www.aquavetmed.info/index.cfm?PID=6

If you don't wish to see a vet, it would be best not to treat the fish with medications that aren't needed. They can weaken the immune system. Goldfish can live for years with such tumors, especially if the tumor is benign. If you ahve more questions, let em know by clicking on REPLY. I hope that whatever you decide to do, it will work out well.

Anna

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