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by on July 14, 2016
Wet/Dry Filtration SystemsOverview
Wet/Dry filtration has become one of the corner stones of a well designed aquarium filtration system. Along with the general aspects of Wet/Dry filtration, this guide covers all of the benefits of this type of system including biological filtration, mechanical filtration, water oxygenation, chemical filtration and sump configurations. From the basic Wet/Dry filter to the more recent advancements in these filter systems, this guide bring the aquarium hobbyist up-to-speed on this very desirable aquarium filtration system.
Wet/Dry filtration is a method of filtration that focuses on providing biological, mechanical and chemical filtration for both marine and freshwater aquariums. Wet/Dry filters get their name because they take water from the aquarium via an overflow system and pass the water through the air over a series of porous bio-material which is usually in the form of plastic bio-balls. While this process gives the filter system its name, the modern Wet/Dry filter system does much more. While the primary task of a Wet/Dry filter is to provide biological filtration, it is also an excellent filter for both mechanical and chemical filtration as well. After siphoning the water from the aquarium via a skimmer or overflow system, the water is passed through one or more chambers containing filter pads or sponges, where mechanical filtration takes place as physical particles are removed from the water stream before they enter the trickle tower portion of the Wet/Dry filter. It is at this point that the water is passed into the trickle tower or bio-chamber where it drops down onto plastic bio-balls that are piled up on top of a plastic grate at the bottom of the chamber. This allows the water to pass through the air as it drips through the bio-ball chamber which creates an ideal environment for beneficial aerobic bacteria to live.
It is these aerobic bacteria living on the bio-balls that perform the biological filtering of the water as they remove waste products from the water and produce oxygen. At this point the water drops down into the main sump area of the Wet/Dry Filter system, where chemical filtration can be added along with other filtration devices such as protein skimmers, activated carbon media and much more. Lastly, the water moves into the final chamber which contains the pump to return the water from the Wet/Dry filter sump back into the aquarium. Since Wet/Dry filters excel at biological filtration, they have become one of the most important ingredients to a successful aquarium filtration system. Biological filtration is the process in which ammonia is converted to the less toxic nitrite, then to the relatively non-toxic nitrate. While nitrate is non-toxic at low levels, it can build up over time and become toxic to most aquarium inhabitants. Nitrate will need to be removed from the aquarium system either through the use of live plants which consume nitrate as food or from water changes where aquarium water is removed and replaced with fresh water that is from a nitrate free source.
Wet/Dry systems earned their reputation as excellent biological filters by the method by which they stimulate bacterial growth. A successful bacteria colony requires moisture, heat and oxygen, all of which are effectively cultivated in properly maintained Wet/Dry filter systems. The temperature of your tank will provide the necessary heat for proper growth, and the moisture is taken care of by the water in your tank. The process of how the water is siphoned from the aquarium surface and trickled over the biological surface is how the Wet/Dry does the rest by providing the correct environment and living conditions for billions upon billions of beneficial aerobic bacteria colonies to live and thrive. Each Wet/Dry filter uses its own type and grade of bio material. Most filters use bio-balls, which are spherical plastic balls which are hollow and have a netted structure that provides large amounts of surface area for beneficial bacteria to live. Other Wet/Dry filter designs use a structure called Bio Bale, which looks like plastic hay, which is also very effective at stimulating the growth of beneficial bacteria. New versions of bio-material and Wet/Dry configurations are popping up within the hobby as filter manufacturers look to further improve on what is already a very effective design.
The initial process of skimming the water from the aquariums surface and returning it via the surface of the water creates excellent water agitation which saturates the water with large amounts of dissolved oxygen. On top of this process, when the water enters the Wet/Dry filter from your tank, it is poured over the biomaterial at a high velocity, as the water flows over the material it mixes with the surrounding air, supersaturating the water with oxygen. It is this mixing affect that contributes to the name Wet/Dry filtration. There are even opportunities within the sump portion of the Wet/Dry filter itself for oxygen to be introduced into the water via the return from a device such as a protein skimmer or by passing over additional filter media or substrates where more beneficial bacteria may be present.
While all models of Wet/Dry filters have mechanical filtration via pre-filters in the skimmer box to filtration trays located above the bio material, newer model Wet/Dry filters are constantly improving on this by providing more physical filtration in the form of micro mesh bags, sponge filters and media pads located in various locations throughout the filter system. Any of the Wet/Dry filter systems commonly available within the aquarium hobby provide not only excellent biological filtration, but top notch mechanical filtration as well. Additional mechanical filtration would only be necessary in the most extreme of cases where the aquarium inhabitants produce large amounts of physical waste.
The Sump
The sump area of the Wet/Dry filter system allows the hobbyist a convenient location to locate chemical filtration, protein skimmers, live rock (saltwater setup), plants, macro algae and much more. It is now quite common for Wet/Dry filter systems to come with expanded sump sections to allow hobbyists to keep a variety of additional filters and even create refugiums and plant based vegetable filters. All of these additional forms of filtration make the Wet/Dry filter a complete all-in-one filtration system that is capable of handling all types of marine or freshwater aquarium setups.
Wet/Dry filtratioin systems are not simply a good option to consider, it has become the ideal starting point for a high quality filtration system that excels in both freshwater and saltwater aquarium installations. Due to their popularity, they have expanded with many different variations of the standard Wet/Dry system with expanded sumps, refugiums, Berlin style setups and many more. Be sure to carefully investigate your options when setting up your next aquarium and find the right Wet/Dry system to fit your aquarium goals.