What Is A Saltwater Aquarium Biological Filter? - The Spruce

Now let’s discuss the basics of saltwater aquarium filtration and its process.
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Most marine aquarium hobbyists strive to maintain excellent water quality through vigorous and frequent partial . But despite this de-emphasis on mechanical filtration, many saltwater hobbyists still utilize at least some form of it.
ROTTER Tube filter for saltwater aquarium. No more sump socks. Check out the video:
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This type of filter provides mechanical, chemical, and biological filtration and they are particularly useful for aquariums that are 40 gallons in capacity or larger. Canister filters are multipurpose filters that may be used in conjunction with supplementary filtration equipment or they can work well as the sole filtration device in a saltwater aquarium. A canister filter consists of a plastic housing, or canister, that contains various types of filter media. A siphon tube draws water from the aquarium into the canister, forcing it through the filter media and back into the tank through a flexible pipe. As water is forced through filter media, solid debris is caught and dissolved wastes are filtered out of the water. Biological filtration media inside the filter give beneficial bacteria a surface on which to grow and reproduce. ROTTER Tube filter for saltwater aquarium. No more sump socks. Check out the videos:
Photo provided by FlickrPowered mechanical filters play a lessened role for saltwater aquariums compared to freshwater
Photo provided by FlickrFor many years, undergravel filters have been the top and most efficient filters for saltwater aquariums.
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As you can see, a saltwater aquarium requires some additional and some additional equipment not found on the freshwater side of the hobby. You'll need to invest in a good quality protein skimmer and some good quality live rock. Live rock is important from a biological filter perspective and if you're using live rock you don't have to use an external filter on the tank. Let the remove the dissolved wastes. The external mechanical may actually become a source of if not cleaned often enough since the power filter just traps waste. The protein skimmer on the other hand actually removes the dissolved organics from the water.The periodic are one of the most important tasks that a hobbyist performs on a regular basis and the process is a little different when you move into saltwater aquariums. Freshwater aquarists generally can remove some of the tank water (say 10%) with an aquarium vacuum and then refill the tank with dechlorinated tap or filtered water and your tank could stay in a great shape if you do this regularly. Saltwater hobbyists can't use the same vacuum (python) do this since the saltwater has to be mixed up days before hand in a separate container. You can use a bucket to mix new saltwater or if you have a bigger tank, a larger holding container can be used.I wouldn't recommend that a newbie start a saltwater tank without live rock. There are just too many benefits to having it in your marine aquarium. It's a great biological filter, provides food for various species, provides hiding places and homes for others and it looks great. There are other benefits too. Check out the article on for more information. Setting up and keeping a marine fish tank stable without live rock can be more difficult than starting one with ample quantities of good quality live rock.This is a topic that you will see differing opinions on. The problem with canister filters is not that they don’t work on saltwater or reef aquariums, they work very well. Any biological filter is going to produce nitrate on a closed aquarium system, it is the natural end product of the nitrogen cycle.A customer recently asked me a question about using a canister filter on their saltwater aquarium. The customer had read on Reef Central that you should not use a canister filter on a saltwater aquarium, especially on a reef aquarium. That they do not work well, and will cause high nitrates.In general, keeping saltwater fish is more expensive and more difficult than keeping freshwater fish. However, once established they do seem to be less demanding and water quality tends to stay better in tanks using live rock. Live plants perform similar (albeit to a lower degree) functions in water filtration in a freshwater aquarium. If you've been keeping freshwater fish tanks for some time now successfully the switch to a saltwater aquarium should not be all that difficult. If you have the desire, the fortitude to do the necessary research before acquiring animals and aquarium equipment and the money necessary to run a saltwater aquarium, then by all means go for it! Once you get started you'll be wondering why it took you so long to get into the saltwater side of the hobby.