Marine Aquarium Filtration

wet dry filtersNot all marine aquarium filtration systems are created equal.  The myriad of choices, especially to the beginner, can be overwhelming. Many saltwater aquariums can get by with simple easy to use, easy to install and easy to afford aquarium filters like hang on the back style or canister style units. Others, like reef tanks or larger saltwater aquariums, will do much better with a bit more complicated system like wet dry filters with or without protein skimmers.


The key is to decide ahead of time what type of saltwater tank you want to setup and maintain.  These decisions include types of fish or invertebrates, size of tank, depth of wallet, and commitment to regular maintenance without making yourself a slave to the aquarium you’ve chosen.  Much of this has been discussed in other posts on this site including: Different Types of Aquarium Fish, Are Saltwater Fish Tanks Hard to Maintain? and Saltwater Aquarium Tips as well as our home page.

overflow filter

Smaller tanks, less than 45 gallons, that have fish only can get by with hang on the back type of filter.  These filters are limited to their capacity because of the media that can be place in them.  They tend to clog quickly and flow rates drop drastically.  Some aquarists will use multiple units if they have larger tanks, but it is usually better to go to a canister style or sump type wet dry filter for aquariums with larger volumes of water.


canister filterCanister filters have both intakes and returns that stick out like sore thumbs in the tank and usually take away from the overall aesthetic looks of the environment.  Many canisters function quite well in saltwater aquariums up to three hundred gallons.  They need to be maintained regularly, about once per month. However, they are not typically recommended for reef or FOWLR (Fish Only With Live Rock) aquariums because of the limited ability to easily manipulate the media to suit the needs of the aquarium and the lack of ability to create high dissolved oxygen content.  Another drawback to a canister is because of their location, normally on the floor or in the stand, if they develop a leak they can cause a huge mess.


The most widely used system marine tanks that are large and / or have live rock and invertebrates utilize is the sump or wet dry filter.  cpr wetdryThey come in all shapes and sizes.  They consist of a over flow box or prefilter that can either hang over the back of the tank or be built right into the tank which is a much better look.  Because these filters are open at the top, it allows the aquarist to place any number of types of media in the sump including but not limited to bio balls, carbon, resins, protein skimmers, etc.  If you plan ahead when setting up your aquarium with a wet dry filter, it is easy to incorporate a heater, chiller, calcium reactor, etc. therefore keeping the tank itself free from clutter and cords so the focus is just on the beautiful inhabitants.


You don’t have to be some devoted scientist that becomes a slave to the tank.  Where’s the enjoyment in that?  But the quality of equipment that you choose can make your life much easier and keep your maintenance time to a minimum. Quality in Quality back! Do some research like you are now and talk to the local store that you get your tank from for the best possible marine aquarium filtration that you can afford.  It’ll pay off in the end.  If presented with two choices of filtration, always go with the size that is larger for your tank.  Under filtering can cause an unhealthy environment.  I’ve yet to see an aquarium that is “over filtered”.

Article Name
Marine Aquarium Filtration
This article attempts to show the reader the choices of filtration that are available for the marine or saltwater fish tank.

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