The bottom filter for an aquarium is also called "false bottom". It provides not only mechanical water purification, but also natural: through the soil. However, this equipment has its advantages and disadvantages.
How does the bottom filter work?
False bottom is a thin but durable plastic plate with many holes drilled in it. On this perforated canvas, which is laid with soil. It can also be made in the form of a lattice with a fine mesh. On the reverse side of the plate, a pump, a system of pipes for a water intake, a filter are reinforced. Bottom filters are equipped in different ways, but they all work according to the same principle: they pump out water from under the ground, clean it and return it to the aquarium.
Pros and cons of the bottom filter
The undoubted advantage of the bottom method of water filtration is high-quality biological and mechanical treatment. The advantage of this equipment is that it is almost invisible under the plate or grate. This is especially true for those who seek to create an aquarium design as close to natural as possible.
In addition, the false bottom allows you to maintain an optimal microclimate for fish. The advantage of this equipment is that it will provide flawless cleaning of the bottom, where fish waste, food, and algae debris accumulate.
If the aquarium is small, the power of the pump will provide an even flow of water. If the tank has a solid volume, any of the bottom filters may not cope with its task, since when the purified water comes out, it needs to overcome the resistance of the upper layer. Therefore, clear liquid can only be found in the lower part of the aquarium, without reaching the top. When using the bottom filtration method, the recommended soil thickness is 5-8 cm.
Another disadvantage of these filters is that they are quite difficult to maintain. To install the bottom equipment in an already operating aquarium, it will need to be completely rebuilt. The soil, laid on a false bottom, must be large enough, since the shallow one is not able to provide the required water current, which will significantly impair its filtration.
Some models of bottom filters are designed with a small gap between the plate with the equipment installed under it and the glass of the aquarium. This is fraught with the risk of the smallest fish penetrating under the falsehood. Therefore, snails, fry, shrimps will have to be removed from under the plate. This also complicates the maintenance of the aquarium.
When using the bottom filter, you should be aware that it clogs up rather quickly and requires cleaning. Experienced aquarists solve this problem by providing a backflow of water with a properly connected canister filter. In the course of its operation, the dirt begins to come out through the soil and rise to the surface of the water. This can lead to a lack of oxygen in the aquarium, so this cleaning is best done with the compressor on.
