Types of Fish Tank Filter

Tips for Buying a Fish Tank Filter

There are two main types of fish tank filters; external tank filters and internal tank filters. Both these types of filters can be used in either fresh water or salt water aquariums.

The various types of external filters that are present on the market are:

Power Filters: This is the most common choice in most cases, particularly for tanks under 55 gallons. It is very easy to set up, easy to maintain and most importantly not expensive.

Bio Wheel Filters: This is another type of filter which is very common on the market. It offers a complete 3 stage filtration system in one sturdy, easily installed and maintained filter. It is the best choice for freshwater and marine tanks up to 75 gallons.

Canister Filters: These type of filters are used in freshwater or saltwater aquariums and are recommended for larger tanks i.e. 30-50 gallons upwards.

Internal Filters: These filters are fully submersible filters that work inside one aquarium. It is useful for small aquariums with bio loads as it does not tend to have large media chambers. In the case of larger tanks they are useful as supplements to an external canister filter. It is also a great choice for the low water habitats like turtle tanks.

External filters are the best choice for any fish tank, if you can afford it. As all the filtering is done outside the tank, it keeps the filtered water separate from the unfiltered water until it is returned to the tank. A couple of long hoses connect the filter to the tank; one supplies the filter and the other returns the filtered water to the tank. This type of filter is the most effective but also the most expensive.

One can purchase any these types of filters at the local fish shop, but one may face harder time to find out the more expensive external type at a general pet store. The external fish tank will cost more up front but in the long run one will save on maintenance costs and fish costs as one will be providing the best habitat that they will live long and healthy lives.

Below are some of the different types of fish tank filters which are easily available on the market:

UGF or Under Gravel Filter – These filters have been used for several years by people with great results. Unfortunately, this kind of filter gets bad press by people who do not know the basic idea and the necessity of maintaining these filters.

UGF filters usually consist of hard plates that sit at the surface of the fish tank. These plates are raised a bit from the surface in order to support the layer of gravel. You can find minute slots in the riser tubes and the hard plates.

A water pump or air stone known as power head is being used to move the water up to the riser tubes. This water then flows through the gravel bed, up the riser tubes and under the hard filter plates. This water brings in oxygen and promotes development of bacteria. All these bacteria’s metabolize nitrate and ammonia in the fish tank.

This results in a very efficient biological filter. Regrettably, the wastage is pulled off into the gravel layer and because of this the gravel layer gets clogged and results in poor quality of water. This is why it is important for you to change the water and clean the gravel regularly. This can be easily done with the help of gravel vac or a siphon hose that allows you to take-out the waste from the gravel surface while changing the water. The UGF filter is cheap and reliable provided you are keeping the gravel surface free of debris.

Wet-Dry or Trickle Filters – These filters are usually placed underneath the stand of the fish tank. Water is then gravity fed to these filters where bacteria beds are supported. These bacteria’s consist of biowheel, biological and other bioballs media. The main point is that all these media’s must be removed out of the fish tank. In this case, water is enabled to trickle over the media and at the same time be exposed to the air. This results in extremely huge particles of bacteria developing which are capable of supporting extremely large sized fish loads. All the trickle filters usually have a pre-filter that serves for the mechanical filtration. In case you have decided to design your own filter then it is necessary that all the bio-media is left out of the water. Covered media normally defeats the intention of having trickle filters and besides that you can even try to use sponge filters.

Sponge Filters – These filters are similar to the biological filters. Water is actually taken out by using a sponge and later pumped into the water column. Since, the water always flows through these sponges there are chances of bacteria developing, similar to the case with UGF filters. Sponge is an expensive product and is competent of supporting large loads in the fish tank provided the fish are small in size. Sponge usually tends to be covered with waste particles and usually required to be cleaned frequently. Cleaning sponge filters can take around half an hour. However, whenever you are changing the water in the fish tank on regular basis, you can even remove the sponge filter and try rinsing the dirty water from the sponge. This allows you to eliminate the waste debris settled on the sponge without harming the bed of bacteria. These sponge filters are excellent forms for fish tanks where the gentle water flow is necessary. These filters are also excellent when compared to biological filters that can be easily removed and replaced for immediate filtration.

Box or Corner Filters – These filters are available in small setups and at an affordable price. However, these filters usually fail to support fish tanks. The specific design of these filters is smaller in size which is filled with filter floss and carbon. Both these units are placed inside the fish tank and are powered by a specific air pump. These units are designed for both chemical and mechanical filtration as they support a small quantity of bacteria until the carbon and floss are changed. One of the best ways to remove the carbon and floss is to replace them with gravel or bio-media. This may allow the growth of bacteria in limited quantity, competent of supporting small loads of fish. These filters also work perfectly for raising fry.

Bio-Wheel Filters - These filters are generally manufactured by Penguin Ltd and combine biological filters with benefits of both chemical and mechanical filtration. These filters usually consist of a particular unit which hangs on the back of the fish tanks. Water is taken into this unit by using an impeller and later discharged into the fish tank. The bio-wheel is the last step included in the process of filtration. It is competent of supporting large loads of fish. These filters also include filter pads which are mechanical. This pad is the initial step of the filtration process. As the water flows through these pads, few large particles of debris are being removed which keeps the filter free of debris. These filter pads have to be changed or rinsed on a regular basis. Inside the pads you have the activated layers of carbon which removes the impurities like odor from the water. This literally keeps the fish tank from smelling fishy.

Power Filters – These filters usually hang on the rear side of the fish tank. Water is usually pulled into these filters and later pushed via the filter pads that contain carbon. This results in chemical and mechanical filtration. However, this type of filter is not a better resource than biological filtration. However there are several other designs which have included a biological filtration pad within the unit and it therefore becomes a complete system for filtration. This includes units such as Millennium, Aqua Clear and Whisper. Besides these, Penguin models are said to be one of the best units for the purpose of biological filtration. Actually, power filters are generally meant to accent the present biological filtration like the under gravel or sponge filters.

Fluidized Bed Filters – These filters are growing in popularity, which is rightly deserved. They consist of a specific cylindrical pipe which is entirely filled with sand. Water is initially taken out through the filters which results in massive growth of bacteria. They are also one of the most outstanding resources of biological filtration which contains a smaller unit. Fish tanks up to several thousands liters can be filtered by using these units. They even require a pre-filter in order to remove particulate matters. However, these pre-filters have to be cleaned frequently in order to allow the file to maintain its flowing rate of water. These are said to be one of the best units that can be used in combination with either the mechanical or power filter of higher flowing rate.

Canister Filters - These filters are quite expensive compared to other filters however they are usually one of the best quality and most efficient filters. Water is usually taken out from the fish tank through the hose and later passed into a container which is tightly locked and rests outside of the fish tank. The water then passes through a number of compartments that enables you to organize the filtration media in the way you want. The water pump later pushes this water back into the fish tank. This filter is quite versatile and enables you to improve chemical, biological and mechanical filtration according to the requirements of your fish tank.