The primary concern of a hobbyist should be the management of biological wastes inside his or her aquarium. Marine livestock such as fishes, invertebrates, fungi and bacteria excrete waste matter that can make the water toxic when not immediately cleaned out or processed. To do that, an aquarium typically relies on its filter system and equipment to maintain balance in a marine environment. Without one, there is no other way by which it can remove fish wastes, decaying matter as well as harmful substances that may cause the water inside the tank to become toxic to the inhabitants. Poor water quality is the consequence of the absence of a filter or the presence of a poorly performing aquarium filter. This often causes the fishes to develop diseases or die.
The key function of an aquarium filter is to trap solid wastes. Through mechanical filtering system, solid wastes are trapped and delivered in a container that allows manual removal of the collected matter. The filtering process can also be done biologically, courtesy of the beneficial bacteria that are found present on all aquarium setups. These friendly bacteria processes the toxins produced by the waste and decaying matter into less harmful nitrates which can be removed during regular water changes. So aside from clearing out the dirt inside the aquarium, filters or filtering systems can also preserve the water quality and disses free tank or aquarium.
Aquarium filtration systems and equipment are classified into two; the mechanical filtration and the chemical filtration systems. Mechanical filtration refers to the mechanical removal of particulate matter from the water inside the tank. It basically removes dirt such as decaying plants and animals, uneaten fish food and fecal waste from the water before it starts naturally breaking down and release pollutants inside the tank. A simple mechanical filter system uses a sponge in which the water is made to pass through and trap dirt. Other more sophisticated mechanical equipment includes canister filters which features an integrated sponge and water pump for high-flow filtering action.
On the other hand, chemical filtration system manages the harmful substances that are dissolved into the tank water. Activated carbon and adsorbing resins are the two most commonly used chemical filters. The adsorbing resins are used to remove phosphate while the activated carbon is focused in trapping small water particles that tend to cloud the water inside the aquarium. The activated carbon chemically bond with the pollutants such as fats, organic acids and more of the offensive chemicals secreted by marine animals.