Description_x005f_x005F_x005F _x005f_x005F_x005F The aquarium filter media ring is suitable for fresh water and sea water tank. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. This product can be used in a variety of filters, pls place in the appropriate position of the filter._x005f_x005F_x005F _x005f_x005F_x005F Features_x005f_x005F_x005F _x005f_x005F_x005F - Color: White._x005f_x005F_x005F - Material: Synthetic material._x005f_x005F_x005F - Size: 1.9 X 1.9 X 2 cm._x005f_x005F_x005F - Our filter rings are an biological filter media for use in Aquarium and Pond Filters._x005f_x005F_x005F - These filter rings are packaged in mesh filter bags - allowing easy cleaning when inside your filter. Alternatively, these can be taken out of the media bag and placed loose in the filter._x005f_x005F_x005F - The huge surface area of these filter rings allow beneficial bacteria to colonize and biologically filter your aquarium water