How good is the biocube's filtration system

[au mister]

I was wanting some feed back on the biocube's filtration system. I use the carbon filter, bioballs, blue filter, and a protein skimmer. The protein skimmer is the oceanic biocube skimmer. I know it is not the best but it does get stuff out. I empty it about every 3 days and it has a yellow tea in it.
Are bio balls good or not. I have heard mixed feelings on them.