When you say overflow, do you mean the random periods of time where the skimmer goes crazy or are you talking about the collection cup just filling with skimmate where it needs to be emptied? All skimmers will overflow if anything foreign is introduced to the tank. As far as not wanting to empty the collection cup, most skimmers have drainage tubes where the skimmate is routed to a different, larger container. Whether or not you need a skimmer is totally dependent upon the nutrient levels in your tank, regardless of your livestock. If your nutrients are high, and other methods of removal aren't working, then a skimmer might be needed. A skimmer is just another tool to keep water clean...whether you use that or another method is completely up to you.
