lets see here....i never skim my 16g reef. all i use on that is chemi-pure. i have a refugium on my 29 gallon reef. never skim that one. and i run berlin turbo skimmers on my xenia farm tanks.
so pretty much all i can say is..it depends on what kind of corals you keep! for instance, gonapora will do better in a tank without a skimmer than in a tank with a skimmer. it all depends on how the water conditions are where the coral originates from. catch my drift?? also, it depends on your set up, and the maintnence program you use on it. if you do weekly water changes, i don't see a need for a skimmer. as a mater of a fact, i NEVER do water changes on any of my tanks!! just top them off everyday! you'll get mixed answers on this one. not everyone is the same on this!