In a tank that small I would stay away from Biopellets, as whatcaneyedo has so expertly stated you run to many risks as you are running a smaller water volume without a skimmer.
Back to your original question, I think a fuge would make an excellent addition to your tank. Not only do they provide great places for the culture of micro life but with the use of microalgae, mangroves and a DSB you can completely eliminate nutrients from your system (The natural way
). A 10g tank drilled will a 5 inch sand bed and a clip on light is cheap and looks amazing alongside a reef tank.