FREE SHIPING USA 29-55 gallon Medium Size Rocket Filter tm (patent pending)THE ONLY AQUARIUM MADE IN AMERICA This filter is a new design from the common box/corner filter that will out perform any sponge filter. It actually pulls the water from the bottom of the aquarium allowing better circulation of the water and it keeps the bottom of the aquarium extremely clean. The water proceeds through small pea size lava rock or pea gravelthen into the clear acrylic chamber were polyester filter fiber removes the finest particulate matter. This filter comes with the media and is ready to use. It can be used in fry tanks without any danger to the fry the only difference is that you would replace the lava rock for aquarium gravel. “Rocket Filters” tm are great in Discus and Angelfish set ups – replacing the sponge filter. Not only will the “Rocket Filter” tm make your aquarium super crystal clear but it is a very good nitrifying filter and you will be able to tell when it needs to be clean by the color change on the fiber material. – No ammonia spikes as you have with sponge filters and will not slime up as sponge filters do. Each filter comes (is packed) with lava rock and floss. Free Shipping USA only. Will ship world wide . . . supply me with your city country and city/country code and I will give you shipping costs.