What is this on my fish

[gpgpgp]

Hi,

My goldfish has had this growing lump on the side of him for a long time now, wouldn’t even be able to estimate how long. It is gradually growing over time and started off as the one singular lump however has spread to a couple of other small spots growing on the same side of his body.

I have another goldfish in the tank with him. The fish has been in there since the start with him and has never showed any signs of catching this. Could anyone help identify what the lump may be and how I can fix it? Would hate to think he is in pain. I have contacted various vets etc but they weren’t sure how to treat it.

Thanks in advance.

 

[the loach]

This looks like Lymphocystis. It is a viral disease that can be diagnosed by examining cells of the growth, they are grossly enlarged.
What is the size of the tank? This is mostly caused by stress due to improper living conditions, there is no cure but improving those.

Also read this http://injaf.org/aquarium-fish/the-goldfish-section/what-size-tank-for-goldfish/