That film on your surface is what you want your aqua c to pick up and if you have a pre-skimmer box on it then you'll be getting most of the gunk out. I believe with all the flow it'll actually make it a bit harder for your skimmer to pick it up since it's not at the surface but thats just me. You shouldn't start a cycle as long as your keeping up with your water changes. I didn't have flow in my tank for a whole year. I would recommend the whisper 40i since their very cheap and you can find the filters for them at walmart or petsmart really cheap. Its very quiet, easy to take apart and clean, and very easy to switch out the filter each week during water changes for a new one. This along with my Aqua C really helps keep my tank crystal clean. You will have to make a slight modification using a piece of wood to help support it since the 47 tall's top lip goes too far out for it. 5 minute project though.