<p>State of the art filter media for use in fresh and salt water wet&#047;dry systems&#046; They may be connected together or randomly placed in the filter box&#046; Bio&#045;Pin Balls help produce turbulence, aiding in the gas&#045;exchange process&#046; The void space between the Bio&#045;Pins is ideal for the movement of gasses like oxygen and allows it to more&#045;readily come in contact with nitrifying bacteria living on the media surface&#046; Biological filtration is the process by which waste is broken down from toxic ammonia to less toxic nitrates&#046; The suggested usage is 1 gallon of Bio&#045;Pin Balls per 20 gallons for salt water or 35 gallons freshwater&#046; SMALL &#045; Each Bio&#045;Pin Ball has 110 Bio&#045;Pins &#040;drip points&#041;&#046; There are 120 balls per gallon&#046; One Cubic Foot of media has approximately 130 Square Feet of surface area</p><ul></ul>