Aquarium Filters and Mechanical Filtration

Saltwater aquarium

The Benefits of Aquarium Filters and Mechanical Filtration in the Saltwater Aquarium.

An aquarium filter is a from of mechanical filtration.  Mechanical filtration the act of removing waste (detritus, uneaten food, plant matter, and other debris) from the aquarium water.

Aquarium filters use filter media such as cartridges, sponges, and floss to remove these waste products. The filter media needs to be changed and/or cleaned on a regular basis. This will prevent detritus and other waste products from accumulating and negatively impacting the water parameters of the aquarium. Poor water quality can be harmful and possibly deadly to marine fish, invertebrates and corals. The key to maintaing a successful saltwater aquarium, is a strong biological, mechanical and chemical filter.

Note: biological filtration depends of nitrifying bacteria, which often grows and lives on the filter media. When you change and/or clean the filter media you are removing the nitrifying bacteria. It will take time for the nitrifying bacteria to regrow and been come effective again.

Mechanical filters come in a variety of forms and I have found combining different styles of mechanical filters within the same system to be very effective. No one filter has all the answers when it comes to performance, so using a combination of mechanical filters in your saltwater aquarium will make it bulletproof.


Types of aquarium filters used in saltwater aquariums:

The Canister filters
Canister Filter

Canister filters pull water up the lift tube from the display aquarium into the canister where the water passes through filter media to clean the aquarium water. The direction of flow varies between models and brands of canister filters. Most canister filters have media that supports biological, mechanical and chemical filtration.

Power Filter


The Power Filter.

Power filters hang on the back of the display tank and draw water up a lift tube and into a filter chamber where the water follows through a series of filter media which can provide biological, mechanical and chemical filtration. After passing through the filter media, it overflows back into the display aquarium.


Sponge Filter

The Sponge Filter.

A sponge filter uses bubbles of air from an external air pump to force water through the sponge. Beneficial bacteria will colonize in the pours of the sponge. This action will produce and establish a great biological filter. These sponges also serve as a mechanical filter, removing larger particles from the water. Some hobbyist use two sponges to make it easier to preserve the beneficial bacteria by replacing the sponges at different times. Sponge filters are often used in quarantine tank.

Under gravel filter

The Under gravel Filter.

Under gravel filters consist of a plastic grate or plate, which lies under the the aquariums substrate. This aquarium filter allows water under the gravel. Water is pulled through the gravel with a powerhead or  external air pump. This produces a biological and mechanical filter. This form of aquarium filtration needs to be well maintained, especially through vacuuming of the substrate.

Wet Dry Filter

The Wet Dry Filter.

This filter design offers a huge impact dissolved oxygen and beneficial bacteria. It consists of a plastic tubes, bio-balls and or live rock rubble.Water flows from the aquariums overflow into the wet dry filters (or trickle filter). The water flows into the top of the wet dry filter. At the top of the tower is spray bar, or distribution plate. A sprays the water across the filter media Once the water has passed through the filter media, it enters the aquarium sump. In the sump water is pumped back into the tank by the return pump.

Aquarium filters and Mechanical filtration in a nutshell.

The main idea behind aquarium filters and mechanical filtration is to physically remove waste particles (detritus, uneaten food, plant matter, and other debris) from the aquarium water of the aquarium. Understanding the basics of biological, mechanical, and chemical filtration, will help you improve your aquarium husbandry and become a successful saltwater aquarium hobbyist.

If you have any questions feel free to contact me at:

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