All I had going on my 10g tank was two little power filters and an extra pump in the tank for more circulation. I had a whisper 10 and penguin mini, I think. They did pretty well as long as I changed the filter pads every week. I was growing sps in there so I would assume it did a good job. I did not have a protein skimmer on the tank.

You really don't need a protein skimmer in a tank that small as long as you have keep up with the weekly water changes. You will have only one fish in there so it shouldn't be overrun with poo. I changed 25% of the tank volume every week and it almost seemed to be a bit much. I'd say on yours, you should change like 2g a week, maybe 4. That should keep everything happy.