Welcome! Are you useing a sump? I built a HOB overflow to drain my 55 into a sump. I had to build an acrylic skimmer box to get the film off of my water surface, since my U-tube obviously does nothing for skimming. You could try building a skimmer box around your intake to remove the film. Also water movement on the surface (i.e. powerhead) will take care of the film, but you are really not removing the proteins that way unless your intake is catching all of the gook.
Personal opinion would be to build a cheap skimmer box. You can even make one out of a plastic container and a dremel tool. You have tons of options and enough opinions on here to point you in the right direction. Good luck and I hope that helps.
Anthony