My scooter blenny has this bulbous red lump on one of its fins. THe fin is one it uses to scoot around. He seems to be happy and still moving just fine, but it looks pretty disgusting and scary. I don't know what it could be, or even what caused it, and I was hoping someone could tell me what the disease is called so I can research it and figure out a possible treatment.
Thank you!
Thank you!