Read how stuff works, check filter tubes and plates, gallon to air flow power, shipping time, customer stars and more! This undergravel filter is suitable for both saltwater and freshwater tanks. There is however a limit for adding the gravel on the undergravel filter which should be around 1 to 2 inches and it also needs to be thoroughly rinsed before being added to the fish tank.
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Undergravel filters, long used in marine aquariums, have enjoyed a surge in popularity in freshwater aquariums in the past decade as the importance of the nitrogen cycle has become apparent. These fish tank filters provide an effective means of minimizing ammonia and nitrite levels in aquarium water, and are simple and inexpensive to install. Because they are hidden from view and perform their task without fuss, they can easily be ignored or neglected.
The gravel can be a good filtration material, especially if there is a substantial layer, more than 5 cm in height, of gravel. The under gravel filter consists of a rectangular grid most cases plastic, but can also be made of conjoined pipes with holes connected with a pipe for water circulation. The under gravel filter uses the gravel as filtration mediathus providing mechanical and biological filtration since the beneficial bacteria usually makes colonies on objects, instead of just floating around in the water like the malicious types; the gravel is perfect for vast colonies of beneficial bacteria.
Biological aquarium filtersincluding undergravel filters, function in a completely different way, and they have a completely different design. The Nitrosomonas and Nitrobacter bacteria necessary for biological filtration will colonize virtually every surface in a tank. However, there is usually not enough surface area in a tank to support populations of these nitrifying bacteria large enough to process all the ammonia that is produced in a typical aquarium.
The under gravel filter UGF controversy has been raging for years. As modernization of aquarium filtration products advances, many aquarists feel the need for a UGF has long past. However, some still feel you can't run your aquarium without one.
Under gravel filters are any filters where the water is drawn through the gravel as the primary filter media. The portion of the filter you will purchase is a plastic grate that keeps the gravel off of the bottom of the tanklift tubes to deliver water, and power heads or an air pump to move the water. Under gravel filters consist of a plastic grate or "filter plate" which lies under the gravel of the tank.