well once is still having da same probelm...da oda one has this white patch on it's fin..it's like...well...it have a swolllen tummy will a swimbladder desiese spread? and will my white patch spread...no it's not ick
I am not sure of what it could be, but here is a link that may help you. It is a link to Cory diseases. You may be able to locate exactly what it is, and how to treat it.