HELP - Fish Illness

[Myanth]

First thing in the morning it is really pronounced and it fades all day, usually by night time it is mostly gone. Today it is really bad. Has been getting worse almost every day. Was thinking it was some sort of predator or maybe a bacterial infection. Infection would get worse daily but why would it fade away at night? My powder brown is hanging out right in the path of one outlet like he's trying to wash something off.