They do indeed have protein skimmers, but they're made exclusively for saltwater tanks, and pretty expensive at 150$ a pop for the nano version. Someone tried using one on his freshwater tank and it simply doesn't work because the machine relies on saltwater to create the many long-lasting bubbles needed for it to function. Basically, the bubbles help to attract the protein film into a "collection cup".
If you have a filter that provides at least some gentle surface agitation, you shouldn't be bothered by the film. As said before, I don't think it's a question of oxygenating the water, either. I have a lily pipe filter output on my current 3.5 gallon and I never see the stuff, but in the unfiltered 1 gallon that was my betta's temp home when I first got him, it was all over the place.