I am thinking of purchasing a protein skimmer for my 20 gallon SW tank. I only have galaxy, green clove polyp, and soon to be frog spawn in there right now (not sure if I'm going to add more, but probably will along the lines of zoanthids). My tank is connected to a 10 gallon sump (around 5 gallons of water) where the protein skimmer will reside. I wanted to just get something basic that gets the job done, and will fit in a small compartment in my sump. I was thinking of the Oceanic BioCube Protein Skimmer which is used on the 14g & 29g gallon biocubes. Would this be a reasonable skimmer? It's only around 20 dollars shipped so that makes me happy. Any other inexpensive skimmers that could handle a light load for a 20 gallon? Currently there are no fish, and the tank has been set-up for around 4-5 months. I was thinking of adding a couple clowns or damsels for fish and some kind of shrimp.