Choosing the best aquarium filters will help keep your tank healthy and your water clean. Aquarium filters work in three basic ways, and can be classified into: mechanical, chemical, and biological. To put it simply, mechanical filtration works by taking out excess food and other debris; chemical filtration takes our foul odors and undesirable colors; while biological filtration converts nitrogenous wastes.

There are different filtration techniques and types, but choosing aquarium filters to make up an effective filtration system can be a challenge. An efficient filtration system should consist of various filters to satisfy most, if not all of the following criteria. First of all, your filter should be quiet. No one, not especially your beloved finned friends, will appreciate a roaring filter day in and out. A good filter also continuously keeps the surface water in motion for sufficient oxygen exchange; and removes floating debris, bad odor, and chemicals from the water. An effective filter should also be able to convert ammonia from fish waste and excess food into nitrate; eliminate harmful algae and parasites, and in some cases, heat water in a tropical ecosystem.

Now, there are specific filters that can satisfy one or two of the above criteria. An under gravel filter (UGF), for example, is one effective system that can regulate temperature, aerate and clarify water, and filter chemically. This type of filter is placed at the bottom of an aquarium, with a thin layer of gravel over, and connected to an air pump. Choosing aquarium filters such as a UGF is an economical alternative as they are also very durable and easy to maintain.

A canister filter, on the other hand, is hung to the aquarium, connects through hoses, and is equipped with its own internal pump and sealed container for catching wastes. The best canister filters have quiet motors and tight mechanical barriers inside to make for better filtration. Standard canister filters also allow for biological, mechanical, and chemical filtration - another great option when choosing aquarium filters.

Filter media, consisting of a cartridge and a bag with carbon can also be an alternative when choosing aquarium filters. A filter media works by mechanically filtering through the bag and collects excess debris, harmful bacteria, and regulate oxygen content in the water. The carbon in the bag is effective in absorbing foul odor and undesirable colors, thereby polishes the water. Nitrate and phosphate absorbers can also be added in the cartridge to work against harmful algae.

For aquatic systems with baby fish, adding sponge filters is a good idea, as these prevent the fish from being sucked into the filter.

Ultimately, the key to achieving a clean, healthy, and well-aerated tank is choosing aquarium filters that go along well with your fish ecosystem. Choosing aquarium filters need not be complicated, this depends on how much research you put into it.