My mother-in-law has a sick, golden veil angelfish in a 130G community tank (other inhabitants are 3 more angels, 3 gouramis, 3 loaches, 2 bala sharks, 6 rasboras, and a few others I can't remember). The tank has been established for about 6 months and has 2 canister filters (Ehiem and another brand). The temperature is at 80F. Both the ammonia and nitrite are at 0ppm; unfortunately, I don't have the specifics for the nitrate. All inhabitants, with the exception of this angel, seem healthy and happy.
This sick angel has the appearance of blisters on him that, after a few days, rupture and leave a hole behind. He has them all over his body, and they initially broke out on his fins and then moved onto his body and head. Other than this odd phenomenon, he is eating well, swimming just fine, and interacting with the other tank mates. He willl be a year old in February (I raised him from an egg after my two angels spawned unexpectedly in my community tank).
Unfortunately, I don't have a picture of him, and I know that diagnosis is much more difficult without an image. Can anyone give us an idea of what this may be and how contageous it is? He's her favorite fish, but she doesn't want to contaminate her community and wants to remove him if it is necessary for the well-being of the remaining fish.
Sorry this is so vague, but just thought I'd try to help her out. Online, she found a description of fish pox that seemed to be the closest to what her fish has, but she wasn't sure. It sounded like hole-in-the-head disease to me, except that this is not confined to his head and did not originate there.
Thanks for any and all suggestions!