I use a Southbay 6-1 skimmer. It is designed exactly after the Euroreef, same pump and everything. Great skimmer.
Sounds like you are thinking low cost HOB skimmers though. Be careful if so. Don't skimp on the skimmer. You'll regret it.
But if this is for your 30g, a CPR should do OK. Kip was correct though, in that you will spend a lot of time taking apart, and cleaning the pump.