Filtration

In general, marine aquariums have more complex filtration requirements than most freshwater aquariums. The various components frequently include Wet and dry filters and Protein skimmers. Protein skimmers are devices that remove organic compounds prior to their degradation, and are also very useful in marine aquariums. Protein skimming is also used in the popular Berlin method that relies on live rock, and periodic partial water changes to degrade and remove waste products. The Berlin method relies on large amounts of live rock being included in the aquarium. The rule of thumb is 1/2 - 1 lb. per 1 US gallon (0.2 - 0.4 kg per 4 liters). Some marine aquariums also include a refugium and/or a sump. Refugiums are small containers, or aquariums hidden behind or beneath the main aquarium and connected to it via a water pump. Refugiums have recently become quite popular among reef aquarists. Refugiums serve several purposes: adding water volume, providing a fish-free site for biological filtration in live rock and/or the sandbed. Fish-free refugiums are host to populations of copepods, amphipods, isopods and other zooplankton. The sump may contain a number of compartments, each with its own filtration material. Often, heaters, thermostats, and protein skimmers are placed in the sump.