Hello dear colleagues and readers! In today’s article we will deal with such an important point as the external filter for the aquarium.
Since this topic is quite popular in the sets of aquarium forums, I will try to answer it briefly and to the point.
Aquarian filters on the principle of operation are: biological, mechanical and physico-chemical. Mechanical filtration removes mechanical suspensions and other dirt from the aquarium, which is washed out of the filter under running water.
The principle of biological filtration is based on the removal of dissolved organic compounds from water.
For this process are responsible colonies of bacteria living in the biofilter. Adsorption filters in which zeolite and activated carbon can act as filter elements adsorb various salts and organic compounds from aquarium water.
In addition, biological filtration can be performed using ozonizers. The principle of their work is based on the oxidation of organic matter.
As you understood from the name, the external filter is located outside the underwater garden, as a rule, it is installed under the aquarium in or near the tank. In view of the fact that the canister has a large volume, it can fit a larger amount of filter materials.
And as a result, in your aquarium better filtering. Since there is enough free space inside the filter, it can be adapted for special materials intended for specific purposes.
Thus, you better adapt the device for a specific type of aquarium.
Basically, external filters are made mixed, that is, they have a department for mechanical water purification, in which they install a synthetic winterizer or a sponge that collects mechanical dirt on itself. In addition to the mechanical cleaning section, there is a section with a special biomaterial in the filter where bacteria reside. Basically, the external filter is purchased for a large volume of aquarium (200 liters or more).
The price of these devices is relatively higher than that of the internal “brothers”.
The internal space of the device is divided into sections. On top is all the mechanics responsible for the operation of the device.
Just below is a compartment with a biomaterial, as a rule, these are ceramic granules and coal, which serve as a springboard for the formation of colonies of beneficial bacteria that maintain in your underwater garden biological balance constant parameters of hardness and acidity. The essence of the biobalance is necessary to know every beginner aquarist who makes the launch of his first aquarium.
As in the internal filters, in the canister there is a compartment in which a large sponge is installed, which carries out biological and mechanical filtration. In more sophisticated models, a water heater is sometimes installed that maintains the set temperature of the medium in the aquarium.
For cans whose volume exceeds 500 liters, it is sometimes advised to install a pair of canister filters.
The advantage of biomaterials is its high porosity. In porous ceramics a large area in relation to the volume.
Anaerobic bacteria settle inside the small pores, which are responsible for the decomposition of nitrates. Just a month after the launch of the device, a film of useful microorganisms participating in the biological processes of the aquarium ecosystem will appear on the porous material.
The key point of biological filtration is the high concentration of oxygen dissolved in water. Since biofiltration is an oxidative process, for its flow oxygen is needed in large quantities. In addition to mechanical purification of water from turbidity, biological filters neutralize various organic compounds, nitrates, nitrites and humic acids.
For a newly launched filter it takes a month to form colonies of beneficial bacteria that will affect the biological and chemical parameters of the water in the aquarium. Mechanical cleaning starts immediately after launch, everything is trivially simple.
Today, the market for aquarium products is very rich in external canister filters. The aquarist has something to choose from, just need to know what characteristics of the device to pay attention to.
First of all, you need to know the performance of the selected product, since this parameter depends on the volume of your can.
- If the volume of your aquarium is small, then first of all focus on the quality of the device and its noise characteristics, since you do not need high performance.
- For aquariums with a volume of 30 to 70 liters, the throughput of the external filter must be at least 300 liters per hour. This performance is enough, even if the underwater garden is densely populated. In this case, the choice can be stopped on the devices of the company Aquael MINI KANI 80 and Tetratec EX 400 /
- For aquariums of another category, the volume of which is 60-100 liters, the external filter should have greater performance. As a rule, this value should be equal to 500 liters per hour.
- For akvasov with a volume of 100 liters and above, the minimum performance of the device must be at least 700 liters per hour. Such powerful filters include products from EHEIM and JBL. Among the “mature” aquarists talk that you can opt for the product of any company, except Tetra. I did not use filters of this company, so I can’t say anything specific about this. But I have met this statement more than once.
Well, it seems that everything I wanted to tell you today. I hope the article is worth your time.