Aquarium Canister (External) Filter – Complete Guide

The filtration system is indispensable for the aquarium. The way to create a successful organic structure in aquariums is through good filtration. Aquarium filters capture solid wastes in the aquarium, make the liquid wastes harmless and bring clean water back to the aquarium environment. This is important for the health and longevity of the aquarium inhabitants.

Continuous water changes in order to keep the aquarium water clean is not recommended in terms of fish habits and health. One of the most important filter systems in terms of maintenance, cleaning, and aesthetics of aquariums is the external filter. The aquarium external filter is important equipment that is positioned outside the aquarium due to its large volume and ensures that the water remains clean.

What Does an Aquarium Canister (External) Filter Do?

The aquarium canister filter consists of two hoses connected to the canister filter box and various apparatus. We can briefly explain the working logic of the canister filter as follows. The water in the aquarium is carried to the filter box by the suction hose, one of the hoses of the canister filter. The water entering the canister filter passes through the filter materials from the bottom of the box to the top and reaches the filter outlet hose and is pumped back into the aquarium. Pumped water enters the filter as dirty during each circulation and reaches the aquarium after being cleaned.

The aquarium canister filter ensures constant water circulation in the aquarium and works for a healthy aquarium. It is very important for fish and other aquarium species to get enough oxygen. The canister filter undertakes to provide sufficient oxygen.

There are some basic materials used in every canister filter. One of them is the ceramic ring. The aquarium ceramic ring traps coarse dirt from the water and allows beneficial bacteria to nest in its pores. There is also a blue thick sponge among the canister filter materials of the Aquarium. This piece of sponge is contained in the filter and traps small debris escaping from the ceramic ring. Again, the substrate is the part where ammonia formed due to residues such as toxic feces, rotted plants, and rotting food is destroyed. There are also canister filter materials such as fiber, activated carbon, zeolite and bio balls that play a role in filtering the aquarium water.

What to Consider Before Buying a Canister Filter

Canister filters used for cleaning water in aquariums are produced and sold by different brands. Among the aquarium canister filter types, there are alternatives with varying circulation rate per liter. In addition to these, there are also models that vary according to the number of baskets in the filter box. However, it is very important to pay attention to some points before purchasing an external filter in order to get the expected efficiency from the canister filter. In this sense, we can list the things to consider when choosing an aquarium canister filter as follows.

Flow Rate

The flow rate of the canister filter is very important for the correct circulation of aquarium water. However, it should be remembered that high flow rate does not mean that the water is cleaned better. On the contrary, in this case, the dirt retention and beneficial bacteria binding coefficient of the canister filter decreases. For this reason, it is necessary to avoid choosing a canister filter with an excessively high flow rate.

Especially for planted aquariums, it is thought that the canister filter flow rate volume should be ten times the aquarium volume. However, this is a wrong determination. Because if a filter with a flow of 500 lt / hour is preferred for a 50 liter aquarium, it will cause excessive circulation. This does not help to clean the water anymore, and it is also very harmful to creatures that do not like currents.

There is no clear answer to the question What should the aquarium canister filter flow rate be? However, by purchasing a canister filter with a flow rate of 3 or 5 times the net volume of the aquarium, an improvement in circulation can be made according to the observations. In this sense, it will be easier to choose among canister filters whose flow rate can be adjusted.

Hand Pump

One of the important points to consider when purchasing a canister filter is the hand pump. The hand pump is an easy product for filling the water into the filter during the setup of the aquarium. But in very cheap models, the hand pump can get stuck. For this reason, if a hand pump model is to be purchased, it is necessary to avoid very cheap canister filter models. Again, in order to avoid such problems, you can choose from canister filters without hand pump. In filters without hand pump, can be refilled with the water remaining in the suction hose.

Filter Materials

When purchasing a canister filter for the aquarium, it should be paid attention to whether it contains canister filter materials such as a sponge, fiber, and biological cleaning material. Because filters that contain canister filter materials are more economical as they do not require any later expense. In addition, only canister filter sponges can be sold at high prices alone. However, the materials in very cheap canister filters can be both poor quality and insufficient. In such a case, the materials inside the preferred canister filter can be changed or better performance can be achieved by adding additions.

Energy consumption

The canister filter is among the aquarium equipment that works non-stop. For this reason, it should be evaluated in terms of the energy consumed while choosing a canister filter. In this sense, it is beneficial to choose among energy-saving canister filter models.

Noise Level

Each aquarium canister filter makes some noise. However, the lower the volume, the better. Because no one can tolerate a canister filter that constantly makes noise at home or at work for a long time. For this reason, canister filter models should be chosen as quiet as possible. Besides, as the price of the filter increases, the sound it makes does not decrease. Even very expensive canister filters can work with noise. In addition, all filters produce sound until they blow the air inside. This situation should not be considered as the filter is making too much noise. Because the sound produced is not the engine sound but the sound of air, and the air will be blown out in a short time and the filter will start operating normally.

Spare Parts Supply

Aquarium canister filters are equipment that can cause various malfunctions over time. Considering this situation, care should be taken to ensure that the spare part of the canister filter is easily available. In addition, spare parts for canister filters should not be too expensive and should be directly proportional to the price of the product. In cases where you cannot obtain spare parts, your filter will be inoperative. Since the filter is a continuously working equipment, brands that can provide spare parts in a short time should be preferred.

Warranty Period

The aquarium canister filter is equipment designed for long-lasting use. However, warranty period of the filter is very important. In addition, it should be ensured that the warranty certificate is signed and stamped to be covered by the warranty. Choosing brands known with warranty coverage will make you feel comfortable in possible adverse situations.

🐠𝙃𝙋 Team
🐠𝙃𝙋 Team
We're just like you - aquarium enthusiasts who love aquatic life! We've been caring for and breeding all sorts of freshwater and marine aquarium fishes, plants, and other pretty little creatures for years. We love sharing our knowledge with other fish hobbyists, and this article you have just finished reading is the best proof of that. You can read more about us here.

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