I have a 3000 gal pond outside and I have had this goldfish for about 3-4 years. Well this goldfish got really fat and I didn't think much about it because the sameone got real fat last year around the sametime (spring) I assumed it was a female and just had bunch of eggs 
. It started sitting on bottom, not eating, well then eventually just died. I took some pictures of it and it looks pretty rough, like a tumor or something? Maybe you can help me, and I hope none of my other goldfish have it, they are all swimming and eating fine. Edit: I want to add, I couldn't see any of this under stuff from my view at looking down into the pond. I only saw some white scruff marks on the side, which I thought may have been from breeding.
. It started sitting on bottom, not eating, well then eventually just died. I took some pictures of it and it looks pretty rough, like a tumor or something? Maybe you can help me, and I hope none of my other goldfish have it, they are all swimming and eating fine. Edit: I want to add, I couldn't see any of this under stuff from my view at looking down into the pond. I only saw some white scruff marks on the side, which I thought may have been from breeding.
