Canister filter looks professional. It will certainly be included in the list of equipment lovers of high-tech aquarium. If you place the internal filter in a hermetic case – a canister – and connect it with a domestic pond with long inlet and outlet hoses, you will get a canister filter. It is good because it takes up little space, usually it is hidden in a stand or behind an aquarium. Performance of canister filters starts from 380 l / h. Such filters are not designed for small ponds.
Canister filters are often used to maintain cleanliness in large, planted aquariums for the reason that they do not spoil the interior with their presence. The water intake hose is hidden somewhere near the back wall, and the drain tube is also unnoticed. Since the canister filter housing is located below the water level, ensuring the tightness of the filter is a very important task. To flush the filter material, the device is disconnected from the hoses. So that at this moment no water is spilled, special locking valves are located in the places of the connectors. The capacity of the canister filter is large enough that it allows the use of various filter materials in it. As a rule, there are 2-3 sieves standing on one another with various fillings inside the filter. First, the water enters the coarse filter, consisting of small ceramic tubes, and is cleaned of coarse contaminating particles, then falls on a layer of activated carbon, where some soluble substances are absorbed from the water. The latter is a foam or fiber filter that prevents particles of coal from entering the pump impeller. The filter material washed by water on all three screens contains a large number of saprophytes.
The package of canister filters often include a perforated tube, which is worn on the output hose. It is fixed above the surface, and water is sprayed by drops, imitating rain. Such a device well saturates the environment of the domestic water body with oxygen and is an effective spawning stimulator for some fish. In an aquarium with plants, as a rule, artificial rain is not used, because carbon dioxide is quickly eroded because of it, and the effect of excess oxygen on plants is mostly negative. All canister filters are equipped with power regulators, a water heater is also integrated in some models.
Canister filters may be indispensable in a large farm amateur aquarium plants. Imagine that you have quite a lot of household ponds installed on racks in a separate room – the aquarium. We will not delve into the details of the equipment of such an economy, and we will only note the choice of filters. Providing each of the reservoirs with a separate filter can be quite expensive, and each of the installed devices will have to be washed. However, all the aquariums located on the same level can be cleaned with one powerful canister filter – it will be enough to spread the input and output hoses to extreme reservoirs, and to connect the whole series of aquariums with pipes for water flow. This filtering scheme is not very suitable for breeding fish, because the infection from one reservoir will spread everywhere, but for aquariums with plants it is quite acceptable.