Dymax Slim Flo is an external hang filter designed to be clipped on any side of the aquarium. Unlike the conventional internal power head filter. This hang filter does not take up space in the aquarium. Beside|Dymax Slim Flo is an external hang filter designed to be clipped on any side of the aquarium. Unlike the conventional internal power head filter. This hang filter does not take up space in the aquarium. Beside|Dymax Slim Flo is an external hang filter designed to be clipped on any side of the aquarium. Unlike the conventional internal power head filter. This hang filter does not take up space in the aquarium. Beside|Dymax Slim Flo is an external hang filter designed to be clipped on any side of the aquarium. Unlike the conventional internal power head filter. This hang filter does not take up space in the aquarium. Beside