Bottom filter is not common in aquariums. It is difficult to clean and requires a primer with excellent water permeability. However, among its advantages is the fact that it does not allow water to stagnate in the ground, which is especially important for plants.
The principle of such a filter is that water is pumped by a centrifugal pump or airlift. To the question – what kind of bottom filter for an aquarium is better, you can answer that the filter that is combined with aeration of water is better.
As for the bottom filter for the aquarium, in this case there is no big difference between the mechanical and biological filtration, since the bacteria settle on the filter material of the mechanical filter.
How to make a bottom filter for an aquarium?
It is not necessary to buy a bottom filter for an aquarium, it is enough to make it with your own hands. To do this, we need three pieces of plastic pipe length, slightly less than the length of the aquarium, a few corners, tubes, plug and expander.
We also need transparent plexiglass so that we can lay the ground on the bottom of the aquarium. All pipes and corners need to be soldered to get a single design.
On the entire area of plexiglass, we need to drill a lot of holes for normal air circulation. It is best to do this drill with a nozzle "feather". First, we make a small hole, putting the nozzle at an angle, then turn it straight and drill.
We also need to make a lot of holes on the underside of plastic pipes, for which we use a drill with a nozzle in the same way.
After that we need to build and solder the structure to further connect it with the filter pump. The pump will connect to the expander.
The finished structure is laid on the bottom of the aquarium, covered with Plexiglas and covered with soil.
Connecting the pipes to the filter and putting it into action, pour the defended water into the aquarium, lay out the decorations and run the inhabitants.