The Best Recommended Materials for Salt Water Filters

There are three basic steps in salt water filters and filtration systems. The first is the mechanical filtration, which usually comes in the form of a sponge and is used to separate un-dissolved from dissolved waste. The second is biological filtration, which helps break down bacteria and ammonia into nitrate. The third and final filtration is chemical, which helps treat dissolved wastes.

  1. Sponge

    • A sponge is the best recommended material when it comes to the first step in salt water aquarium filtration systems. The first step is a mechanical step in which undissolved wastes such as excess food or fish feces get trapped in the filter. A sponge will collect that material while allowing water containing dissolved wastes move on through the filtration process. Because sponges will get full of these undissolved wastes, they must be removed and cleaned out at least once a month and completely replaced at least once or twice a year depending on the size of your aquarium and the number of fish in it.

    Bio-Media

    • Bio-media or biological media is a nitrifying bacterium that works both on the undissolved wastes that get trapped in the mechanical filter and dissolved wastes that contain microscopic, ammonia-producing bacteria. This is the second, biological part of the saltwater filtration system. Nitrifying bacteria eat the undissolved waste trapped in the mechanical filtration and produce nitrates as waste. The nitrates then kill ammonia-producing bacteria and balance the pH levels within the aquarium. Depending on the size of your tank and/or the number of fish in it, you need to replace the bio-media at least once a year in order to help maintain pH balance.

    Charcoal

    • Charcoal is the most widely used and best material for the final step of the salt water filtration system. This is the chemical filtration process in which dissolved wastes such as fish urine and excess amounts of ammonia or chlorine are "cleaned" out of the water. The charcoal, which is porous will have contaminated water pass through it but will chemically attach itself to the wastes. The charcoal must be removed and washed at least once every couple of weeks and completely replaced at least two or more times a year depending on the amount of fish and the size of your aquarium.