WhatCandida now that sounds like something seperate to brewing ha ha sounds like something i might end up with after a big night on the town.However the only infection that I know like your oily film is the candida mycoderma.. but , if your film doesn't break in many white points when you move it , Enjoy your beer
Dont wanna drink that stuff not sure what that sorta infection might taste like in the homebrewing department but keen to stick clear of it more of a hop flavour fan.