I think at this point,you would be better off getting rid of the CC substrate,and replacing it with a deep LIVE SAND bed.At least 4".Then adding alot more live rock.You should have around 1-1 1/2 lbs per gallon...This will build up your biosystem,and give your tank alot more stability in the long run...Maybe after this is done,you will find that the filter you now have IS good enough...The sand and rock will be doing all the bio filteration,,,the skimmer will be pulling out all the disolved organics and excess nutrients,and your penguin will only be a mechanical filter...