The above description can take many shapes and forms, and the myriad of hobbyist skimmers available on the market suggests this is true. However, my basic description above doesn't look like many of the skimmers on the market today, and this is where hobbyists get confused. With so many skimmers on the market, which one is the "best one" for their tank? The bottom line is there is NO one best skimmer. Many hobbyists are looking for the perfect skimmer, one that will remove all the organic waste in the tank water, a skimmer which is compact in size, inexpensive to run, and requires virtually no maintenance. In reality, what skimmer to use is truly a guessing game. What we do know is that different skimmer designs equate to different levels of effectiveness at removal of waste. The confusing part comes when hobbyists are confronted with manufacturer's advertising, claiming their skimmer is superior over all the rest because of some 'new' skimming technology. Claims such as, "The "Cycloskim2000" which is 18" tall, will easily skim your 100gal fish tank, and only requires 1 watt of electricity to operate," are rampant in manufacturer's advertisements. So, how do we separate what's truth and what's advertising? For me, one of the least complicated ways to understand which skimmer to buy is to understand a few of the theoretical basics of skimming and then apply this theory intofunctional reality. In chapter 9 of the textbook Aquatic Systems Engineering: Devices and How They Function, P.R.Escobal 2000 [3] Escobal presents a few theoretical concerns that should "shape" the efficiency of a skimmer. These are presented in original form in Table #1.