I think you're fine to leave it at the shock level that you're currently running--the "shock plus" is mostly for mustard algae. I don't know the source of the film that you're speaking of, but usually foam/film will not settle down to the bottom--it takes filtering and chlorine to remove.

Usually, we recommend that you leave the filter running until the algae is dead, and until the filter has taken out everything it can--and at that point, THEN try turning the pump off to see if the remainder will settle. However, in your case, I just noticed that you have a 1.5 hp pump on a 7600 gallon pool--that's a HUGE pump for that amount of water, and if your filter is undersized for that pump, you might be better off just to put the pump in recirculate mode until all the algae is dead and you're no longer losing chlorine, and then turning it off, letting it settle, then vac'ing it out. Have you and one of the equipment folks (mas985, Pooldoc, etc) talked about your filter/pump match already?